Building a System
Your teacher has already germinated seeds for you.
Bergerson's Handi-Wipe System
Perlite, Nutri-Leaf, Handi-Wipe Material Safety Data Sheets
Using the Directions below you are going to create a passive hydroponics system. Your teacher will have
supplies ready for you, but make sure you check the materials list before you get started with construction.
Soda Bottle Passive Hydroponics System
Introduction:
These bottle systems are:
*Passive (no pumps or electricity)
*Closed (the nutrient solution remains in the system)
*Liquid/Aggregate
(Roots can grow initially in the aggregate then
directly into the solution)
Materials:
*2 liter soda bottles
*Scissors
*rubber Bands
*Duct Tape
*Cotton wick Material such as yarn, kite string, etc. about 16 inches per bottle.
Handi Wipes cut into one inch strips are excellent as well.
*Perlite to fill the cup or inverted bottle
*Water and hydroponic specific fertilizer – premixed powder of liquid to fill bottle
*Lettuce Heads or seeds
Method:
Wick System: Nutrient is wicked up the roots from the bottle below.
1)
Cut the soda bottle using the scissors eight inches from the bottom and use the
inverted top as a holder for the Perlite and roots. You can cover the cut edges with duct
tape that will also help keep the top from slipping down into the bottle.
2)
Leave the cap on the top
3)
Thread the wick material through the hole so that half of the wick is on each side of
the cap.
4)
Invert the bottle top and fill with Perlite (weaving the wick material
through the Perlite.) Plant cuttings or seeds in the Perlite.
6)
Mix nutrient solution in bottle
Nutrient Solution Recipe:
Fill the bottle four inches deep with water
Place ½ teaspoon of NutraLeaf 20-20-20 fertilizer in the water….mix
thoroughly…(this will give you an electroconductivity reading of ~1120ppm)
7)
Fit the inverted top with the Perlite into the soda bottle letting the wick material hang
into the solution
Optional:
Your teacher may ask you to record the growth of your plants. If that is the case this page will
walk you through creating an Excel Spreadsheet to do that. Here is an example of a Plant Growth data
sheet. Once all of your data is collected you will complete a Plant data summary. After you have completed
your work you need to either print it out and turn it in, or email it to your teacher. Your teacher will tell you
which method they prefer.
Assemble the Hydroponic Apparatus
This type of hydroponic apparatus, known as a wick system, is one of the easiest ways to grow things
hydroponically. It does not require a pump; it draws the nutrient solution up to the plants' roots by
capillary action in strips of felt. You will need to build at least one hydroponic apparatus for every
different type of nutrient solution you are using.
Materials needed per hydroponic apparatus:
one plastic container, about 12 x 7 x 5 in.
two little pots, about 4-4.5 in. diameter
four strips of white felt, about 3 x 6 in.
two thin boards, about 2 x 8 in.
shrink wrap, plastic wrap, or other waterproof covering
sharp knife
Perlite
First, prepare the platforms on which the pots will sit. Wrap each of the thin boards with the
shrink wrap or waterproof covering. Seal it with tape if necessary; the board needs to be as
waterproof as possible. If you do not do this, the nutrient solution will soak into the board
and soften the wood, causing the board to bend, lower the pot deeper into the solution than
it should go, and possibly break.
After the boards have been waterproofed, you should thoroughly wash the boards, plastic container,
and pots with soap and water. Then disinfect them by rubbing them down with rubbing alcohol or
another chemical cleaner such as Lysol. This kills any microorganisms living in your equipment that
could infect your plants.
Cut two long, narrow slits near the outer edge of the bottom of each pot as shown in
this diagram. Pull the strips of felt through each slit so that they are about half in the
pot and half underneath the pot. Place each pot on a shrink-wrapped platform so that
one strip of felt hangs down on one side and the other strip hangs down on the other.
Then place both platforms on top of the container so that they hang across the
container. Fill each of the pots about 2/3 full with Perlite; be aware that some may
leak out through the slits in the bottom of the pots. Label each hydroponic apparatus
with the type of nutrient solution it will contain.
Step Two: Create Appropriate Growing Conditions
Plants will grow best when they are subject to certain conditions. While it is best to keep conditions
consistent throughout the experiment, certain conditions are hard to control and may fluctuate. The
important thing is that the conditions must be the same for all the plants at any given time, regardless of
how they change over time, because they are controlled variables in the experiment. The easiest way to
keep the controlled variables under control is to put all the plants next to each other in the same
location. Note that you can do an experiment by varying one of these conditions. However, if you do
that, you must use the same nutrient solution for all the plants and keep all the other conditions the
same. This keeps your experiment from having more than one independent variable.
Light:
You should make sure your plants get around twelve hours of light. This is not exact; a few hours more
or less will probably work fine. Since plants get their energy from light, they must have exposure to the
sun. However, they should probably not get light 24 hours a day because such unnatural conditions
may disrupt the normal growth of the plant. You may also substitute a grow light for natural sunlight;
be sure to put it on a timer to simulate day and night for your plants.
Temperature:
Ideally, the temperature should be somewhere between 55° F and 85° F. The optimum temperature may
be different for different kinds of plants. A temperature-controlled environment would provide the most
stable conditions, but if your plants are in a less stable environment, a heater would help to keep the
temperature under control. If the environment gets too hot, you might want to shade your plants and/or
put ice cubes in their nutrient solution to keep them from dying in the heat.
Humidity:
The relative humidity must be at least 45%, and ideally it should be between 60-75%. This can be hard
to control, but if you know your air is dry, your plants will benefit from some artificial humidity. This
can be done with a hoochie-coochie machine (a silly word that means a vaporizer). The hoochiecoochie machine will make water vapor more slowly when the air is relatively humid already, so it
would not be a bad idea to leave it on all the time. Another way to raise the humidity is to spray water
all over the place with a hose or spray bottle. However, this has the undesirable side effect of soaking
everything around your experiment which you may not want to get wet.
(Note: The term "hoochie-coochie machine" was coined by Miss L, our AP Biology teacher who could
not think of the word "vaporizer." No members of S.H.A.R.P. were responsible for this. We used it on
our web site because we think it's kind of funny to say.)
Other conditions:
Factors such as ambient noise, air quality, etc. can also influence the growth of plants. Be sure to keep
all other such variables controlled for all your plants.
Source for this section: Casana, Maritza. [email protected]. "Práctica de producción de hortalizas bajo la
técnica de hidroponía en agua y perlita." 7 Jan 2001. Personal e-mail. (14 Jan 2001).
Step Three: Germinate the Seeds
Before you germinate the seeds, you must choose what kind of plant you want to grow. If you already
have a plant growing in soil and you want to simply transfer it to a hydroponic medium, you can skip
this step. If you are growing from seeds, you need to choose what kind; we recommend lettuce, beets,
tomatoes, celery, and obviously radishes. Other kinds of plants would probably work well too. Note the
growing time listed on the package of seeds you use; it determines the length of your experiment.
Ideally, you should use seeds with the shortest growing time possible. You should also allow lots of
extra time in your experiment in case the plants grow slowly or something else goes wrong.
Source: Casana, Maritza. [email protected]. "Práctica de producción de hortalizas bajo la técnica de hidroponía
en agua y perlita." 7 Jan 2001. Personal e-mail. (14 Jan 2001).
Materials needed:
seeds
clean petri plates
paper towels or cotton balls
spray bottle
You will need to use enough petri plates to hold the amount of seeds you want to
germinate. You should germinate at least twice as many seeds as you want to
actually grow because some of the seeds might not germinate and some of the plants
might die.
Instructions for each petri plate:
Line the petri plate with a layer of cotton balls or paper towels. Place the seeds on the cotton or paper
towels in the petri plate, leaving about 1 cm of space between them. You may want to leave even more
space for larger seeds. Spray the petri plate with water using the spray bottle until the cotton balls or
paper towels are throughly soaked. Put the lid on the petri plate and leave it in the sun for the seeds to
germinate.
Put a rubber band around the petri plate to hold the lid on tightly. This keeps the petri plate
from falling apart if someone knocks it over by accident. It also keeps the petri plate from
opening when the seeds germinate and the little plants get so big that they push on the lid.
If the lid opens, the water will leave the petri plate and the little plants will dry out and die.
(The members of S.H.A.R.P. learned this lesson the hard way.)
Step Four: Plant the seeds in Perlite
When the seeds have germinated and the little plants are about 1.5 inches long, you should remove
them from the petri plates and plant them in the Perlite in your hydroponic apparatus. Before you do
this, you should prepare the nutrient solutions in your hydroponic apparatus. Do this as described in
Lesson Three: Add the appropriate amount of each concentrated part to the 2-Liter mixing bottle and
fill the bottle to the top with deionized water. Then pour the contents of the mixing bottle into the
plastic container in your hydroponic apparatus. You will probably need to mix more than one bottle of
each solution to fill the container; the container should be filled as high as possible without spilling the
nutrient solution.
Before you finish filling the container, pour some of the solution in each pot with Perlite on
each of the felt strips. This "primes" the felt strips so their capillary action is more effective.
You may also want to save some nutrient solution to pour on your plants after you plant
them in the Perlite.
When the nutrient solution is ready in the containers and has been poured through the Perlite and the
felt strips, you are ready to plant the little plants. Plant four plants in each little pot with the roots
submerged in the Perlite and the shoots poking up toward the light. Plant the plants fairly close to the
felt strips so they have easy access to nutrient solution, but do not plant them closer together than about
one inch. You may want to save any extra plants you have by growing them in soil or in more Perlite
somewhere else in case something goes wrong with the plants you have planted.
Check the environmental conditions to make sure they are appropriate: Make sure the plants are getting
about twelve hours of light (give or take a few) from the grow light or the sun. Make sure the
temperature is between 55-85° F. Make sure the relative humidity is at least 45% and ideally between
60-75%. Your experiment is now set up and going!
Source: Casana, Maritza. [email protected]. "Práctica de producción de hortalizas bajo la técnica de hidroponía
en agua y perlita." 7 Jan 2001. Personal e-mail. (14 Jan 2001).
Focus Questions
•
•
•
•
•
•
•
•
•
•
•
•
How does the nutrient solution get from the container to the roots of the plants?
Why must you wrap the supporting boards in something waterproof?
Why must you disinfect all your equipment with rubbing alcohol or a chemical cleaner?
Describe the hydroponic apparatus.
Why must the environmental conditions stay the same for all the plants?
What light conditions do plants like best? How do you control this?
What temperature conditions do plants like best? How do you control this?
What humidity conditions do plants like best? How do you control this?
What is a hoochie-coochie machine? Why might you need one?
Describe the process of germinating seeds.
Why is it a good idea to rubber-band the petri plates shut?
Why should you pour nutrient solution on each of the felt strips?
HOW TO BUILD A SMALL LETTUCE RAFT SYSTEM
This is a lettuce growing machine! If you start some new seeds every 30 days, and replace each
head of lettuce as you harvest with a new baby seedling, you can have a perpetual supply of
crisp, healthy salad greens. The setup we provide here can grow six heads of lettuce at a time,
and the whole unit costs less than $50 in early 2009 (not including a lamp and food).
Most of the materials are available from Home Depot or Walmart. A few items must come from a
hydroponics supplier (but we give you a good cheap source).
SUPPLY LIST:
Shallow reservoir pan (Sterilite 34 qt Latch Box tote works well) this bin is about 23½ X
14½ X 6” deep on the inside [Walmart]
Can of cheap flat back spray paint [Walmart]
Aquarium air pump, 6 feet of airline tubing, “T” connector & 5” airstone [Walmart]
Rigid styrofoam sheet, 1-1/2 to 2” thick; cut a piece to fit inside the reservoir pan. You can
buy a 4X8 foot sheet at Home Depot for about $15. It seems a shame to buy a huge sheet
of it for one little piece, but you can always save it for use later when you are ready to
build your big 2X4 foot lettuce raft! An alternative is to cut a slab from an old styrofoam
ice chest of the right thickness.
6- 2” net cups: http://www.hydroponics-simplified.com/cheap-hydroponicssupplies.html#raft
Small bag of LECA (Hydroton or clay balls), [hydroponics supply or ebay]
© 2009 http://www.hydroponics-simplified.com All rights reserved. Page 1
Styrofoam building insulation, 2” thick
TOOLS NEEDED:
Power drill; 1-3/4” or 1-7/8” hole saw & a 2” hole saw
(Borrow a hole saw kit or buy one, you will definitely use it again).
Jigsaw, coping saw, or table saw to cut the styrofoam
Here's how to build the system:
1. First cut the styrofoam raft to fit inside the reservoir bin; use a jigsaw, cutoff saw, table saw or
even a handsaw. The piece needs to be just a tad smaller than the inside of the bin so it will easily
ride up and down a couple of inches without binding (when the water level drops). This is
important for the raft to work right. But, you do want it to cover the top of the water as lighttight as possible. In our case, for this Sterilite bin, we cut the styro piece 14-1/4” X 23”.
© 2009 http://www.hydroponics-simplified.com All rights reserved. Page 2
Warning: Cut the styrofoam outside in the yard. You can thank me for this tip right now...
2. You will likely need to round off the corners so the raft will ride up and down freely in the bin.
Take care with your block of styro, treat gently, as it is easy to bust it.
3. Mark off the styrofoam block for six holes, evenly spaced, so that there is six inches between
each hole, both ways. It doesn't matter if plants ride over the sides a little, just so they don't
crowd each other. So for our 14 ¼ X 23” block this is how we centered the holes:
© 2009 http://www.hydroponics-simplified.com All rights reserved. Page 3
4. Now cut the pot holes in the styro block. Start with the 2” hole saw first. From the UP side of
the raft, cut a shallow 2” hole, centered over the marked center holes. Cut all 6 holes just to a
depth of about 1/4”, then switch to the 1 7/8” hole saw to finish up. (Our set did not have 1 7/8”
so we used 1 3/4”). Using the center hole as a guide, now cut down as deep as the hole saw will
let you go. Do all six from the UP side of the raft. Then use a nail to go down thru the center holes
and pierce the back side of each hole. This is so you will know where to drill next from the back
side. Then cut with the same size hole saw from the backside of the stryro block all the way flush.
5. Then carefully pull out the cut plugs and clean up the holes a little. Try out the net pots. You
want them to sit in nicely and bottom out at the bottom of the styro, but not fall through.
6. Next, spray paint the outside only of the clear reservoir bin, to make it light proof (prevents
algae). Spray several coats and use the entire can. Do not spray the inside of the bin.
© 2009 http://www.hydroponics-simplified.com All rights reserved. Page 4
Just about ready to load this baby up!
7. Set up the tray on a sturdy level support, (it's final resting place). Fill with 6 gallons of water.
Place the airstone in the bottom of the tray, connect to the air pump, and plug it in to test it.
Important tip: Place the air pump higher than the reservoir to prevent nutrient from backing up
into it.
8. Next, add your favorite nutrient solution to the vat. If you are using GH Flora Series
(recommended), add 6 tsp. each of the Flora Grow, Flora Micro & Flora Bloom, (one at a time, in
that order). Adjust the pH with a test kit (more on this and ordering info in the Tips 'N Techniques
section below).
9. Next, float the styrofoam raft on top of the nutrient solution. You want it to ride at the very
top, so add more solution if your bin requires more than the 6 gallons.
10. Time to transplant your baby seedlings into the raft. Place the starter plugs into the net pots
and carefully pack around them with LECA (clay balls) to help support each plant in its pot. Push
the little net pots into the pre-cut holes in the styrofoam raft.
© 2009 http://www.hydroponics-simplified.com All rights reserved. Page 5
11. Plug in the airstone bubbler and watch 'em grow!
This is about 14 days after transplanting:
© 2009 http://www.hydroponics-simplified.com All rights reserved. Page 6
And this is full grown lettuces 22 days later.
We had been harvesting the outer and lower leaves of these Romaine lettuces for salads. We went
out of town for the weekend, forgot to leave a fan on, and the poor darlings bolted! (Went past
their prime 'cause it got too hot). You can see how the leaves are drooping out instead of nice and
tight. We harvested the whole raft after we took this picture and had an enormous Caesar salad.
Yum!
This is a photo of a different type of lettuce from our large raft. Just wanted you to see what
happens to the roots. They grow down into the solution reservoir. Sweet, neat and clean.
Now continue on for the very important Operating Tips 'N Techniques:
© 2009 http://www.hydroponics-simplified.com All rights reserved. Page 7
LETTUCE RAFT SYSTEM OPERATING TIPS 'N TECHNIQUES
LIGHTING:
You can use just the light from a sunny window if all you are growing are herbs. Anything else
requires some supplemental lighting. A T5 compact fluorescent “grow light” will do fine for
houseplants, herbs, and leafy green veggies like lettuce. This one is available for under $75,
including the 125 watt compact T5 bulb:
You can order this lamp and bulb here: http://www.hydroponics-simplified.com/cheaphydroponics-supplies.html#lighting. You can get off much cheaper by getting a fluorescent “grow
stick” at Walmart for about $25, but you will not get the lush growth a better light setup will
produce. Also, for best results, upgrade to the 200 watt bulb listed on our supplies page.
Learn more about hydroponics lighting here: http://www.hydroponics-simplified.com/hydroponiclights.html. One final note: the grow room must be kept cool for lettuce. Use a fan on low in
there to cool it down.
NUTRIENTS:
We highly recommend the Flora Series nutrient solutions put out by GH (General Hydroponics).
This stuff is superior, easy to use, and reasonably priced. It consists of 3 parts (Flora Grow; Flora
Micro; and Flora Bloom). If you have hard water, get the Hardwater Flora Micro instead. For this
lettuce garden, order a quart of each of the three solutions: http://www.hydroponicssimplified.com/cheap-hydroponics-supplies.html#nutrients. Stick with Flora Series, follow the
label directions, and you can't go wrong!
The nutrient solution must be kept cool (55-70°). This is especially important for the cool-season
crops like lettuce. Learn more about hydroponics nutrient solutions here:
http://www.hydroponics-simplified.com/hydroponic-solution.html. We also provide a nifty little
mixing chart for the Flora nutrients you can print out and save.
As the nutrient level drops in the reservoir bin, you need to periodically add water only (not more
nutrient). Keep track of how many gallons you top up with. When you have replaced a total of 3
gallons of water, stop topping up and let the level drop down quite a bit. Then drain the bin and
mix up a whole new batch of nutrient solution. Each new 6 gallon batch should last 4-5 weeks, or
a whole growing cycle for a crop of lettuce.
© 2009 http://www.hydroponics-simplified.com All rights reserved. Page 8
pH- It is a very good idea for any serious hydroponics project to keep the pH of the water in the
proper range, which is 5.5 to 6.5 (6.0 is ideal). If the pH is out of range, some of the nutrients get
“locked out” and the plants suffer. GH puts out a simple test kit with pH up & down solutions
cheap. It will last you through many gardens: http://www.hydroponics-simplified.com/cheaphydroponics-supplies.html#nutrients.
GROWING MEDIA:
The growing medium for a lettuce raft is actually the grow sponge or cube the seedlings started
in. Then the Hydroton balls are jammed in around the seedlings to help support them in the little
net pots. Large pots are not needed because the roots quickly outgrow the pots and extend down
into the solution.
This is a handful of Hydroton clay balls:
Here is a cheap source for your hydroponics media: http://www.hydroponicssimplified.com/cheap-hydroponics-supplies.html#media.
Hydroton balls must be ordered from a hydroponics supplier. For the tiny bit needed for this small
raft, try ebay for a small bag of it. Learn more about hydroponic growing media here:
http://www.hydroponics-simplified.com/hydroponic-growing-medium.html.
© 2009 http://www.hydroponics-simplified.com All rights reserved. Page 9
We hope you will try out our plans for a cool little lettuce raft system. You will be amazed at the
quantity of produce you can reap from this unit. It provides a great introduction to hydroponics for
adults and children alike, and it's just plain FUN.
The lettuce raft makes a classic science fair project. Use a 10 gallon fish tank instead of the black
tray we use here. Cover the glass sides of the tank by taping thick paper or cardboard to block
out the light (this prevents algae). Then remove the paper covering when you are ready to display
the lovely roots for all to see!
Our guess is that once you get a taste of hydro in this way, you will go on to bigger and better
things. This field of horticulture is wide open! There are many different methods for you to try,
and you'll just get more knowledgeable and skilled at it as time goes on.
You might try growing heirloom tomatoes, medical herbs or even orchids. Or you might just enjoy
munching on your own healthy, homegrown salad micro-greens! No matter which way your
interests take you, you are sure to enjoy this clean, healthy, prolific, earth-friendly gardening
method. We just love hydroponics and know you will too.
Visit our website: http://www.hydroponics-simplified.com often for updates on equipment,
lighting, nutrition, plants and seeds, pests, grow-closets, and plans for several other different
growing systems. We provide simple information, insider secrets, and easy-to-follow instructions
to get you up and growing in no time...
Enjoy!
Simon & Stella
Disclaimer: Many of the clickable links in this ebook are affiliate links, meaning that
if you buy through one of those links, we receive a very small commission (just about
enough to keep the website up and growing!).
Rest assured, however, that we use these products often and highly recommend
them. If you see it here, rest assured that it has our personal stamp of approval!
If you do choose to order supplies through our links, please accept our thanks for
your valued patronage.
© 2009 http://www.hydroponics-simplified.com All rights reserved. Page 10
HOW TO BUILD A SMALL WICK SYSTEM
We recommend a “store-bought” module for this super-easy hydroponic project, the AutoPot®.
AutoPots® are patented kits which are essentially “self-feeders”. They can be used for hydroponic
setups (no soil) or can be planted with traditional potting soil. The heart of the unit is the special
“Smart Valve”, which regulates the flow of nutrient solution into the holding tray.
When connected to a simple gravity-fed reservoir, the Autopots® automatically provide irrigation
to plants on-demand, then remain closed until the medium dries somewhat. This simulates the
wet/dry cycle of natural rainfall, and makes for a very productive system.
We have included this system in our free hydroponic plans not so much as a “build it yourself”
project, but because we wanted to introduce you to this amazing system. Some very successful
commercial greenhouses are set up with nothing but rows and rows of AutoPots®.
© 2009 http://www.hydroponics-simplified.com All rights reserved. Page 1
Our instructions here provide two large pots, and the total cost is about $60 (not including a lamp
and food). You can easily add more modules later to make a whole “AutoPot® farm” if you would
like.
SUPPLY LIST:
AutoPot® basic module (comes with grommet and 1/4” tubing): http://www.hydroponicssimplified.com/cheap-hydroponics-supplies.html#closet
*Please note the new generation Autopots® are square, they look different from our
photos here, but it's the same product.
Extra 1/4” black irrigation tubing if a longer length is needed [Home Depot]
2 gallon bucket [Walmart]
Growing medium: 50/50 Coco coir & perlite: http://www.hydroponicssimplified.com/cheap-hydroponics-supplies.html#media
TOOLS NEEDED:
Power drill; 1/4” drill bit
Here's how to build the system:
1. Using the power drill, drill a 1/4” hole near the bottom of the bucket. Carefully seat the
provided grommet into the hole, making sure it flares out evenly inside and outside the bucket.
Push one end of the 1/4” tubing into the grommet so it extends only about 1/4” inside the bucket.
2. The bucket is going to be the nutrient reservoir, so it must sit up higher than where the
© 2009 http://www.hydroponics-simplified.com All rights reserved. Page 2
AutoPot module will reside. The fluid is gravity fed into the AutoPot trays. No pumps, no timers,
no aerators! Now insert the other end of the tubing to the inlet port on the AutoPot. Just follow
the instructions provided. Guess what? You just built an AutoPot® hydroponic system!
3. Now test the pot for proper operation of the Smart Valve. Pour some water into the holding
bucket. Water should slowly fill the holding tray below until it reaches a level of about 1”. Then it
should cut off.
4. Filling the pots- Each kit comes with a round “root mat” which sits in the bottom of each plant
pot. It keeps the medium in and helps wick up the nutrient solution to the plant roots. The
growing medium is actually the “wick” for this hydroponic system.
The recommended growing medium is:
50/50 Coco Coir and perlite. You cannot use LECA (clay balls) in the wick action AutoPots. More on
growing medium and ordering info in the Tips 'N Techniques section below.
© 2009 http://www.hydroponics-simplified.com All rights reserved. Page 3
5. Plant your young seedlings in the pots and place the pots in the holding tray. You are ready to
rock 'n roll now, time to add food.
6. Nutrient solution is a pretty care-free chore in this system. Because the fluid is not re-used,
once mixed, you don't have to worry about strength or pH. Mix it and forget it! A 2 gallon
bucketful will last several days, depending on the size of the plants and the climate.
So mix up a 2 gallon batch of your favorite nutrient formula, then adjust the pH (read our
recommendations below). That's it... watch it grow!
WICK SYSTEM OPERATING TIPS 'N TECHNIQUES
LIGHTING:
You can use just the light from a sunny window if all you are growing are houseplants. Anything
else requires some supplemental lighting. A T5 compact fluorescent “grow light” will do fine for
houseplants, herbs, and leafy green veggies like lettuce. This one is available for under $75,
including the 125 watt compact T5 bulb:
You can order this lamp and bulb here: http://www.hydroponics-simplified.com/cheaphydroponics-supplies.html#lighting. You can get off much cheaper by getting a fluorescent “grow
stick” at Walmart for about $25, but you will not get the lush growth a better light setup will
produce. For best results, upgrade to the 200 watt bulb listed on our supplies page.
If you are interested in fruiting veggies like tomatoes, or serious herbs, you will have to upgrade
to an HID lamp. Learn more about HID lighting and see our special combo lamp deal here: http://
www.hydroponics-simplified.com/hydroponic-lights.html. One final note: the grow room must be
kept cool. Use a fan on low in there to cool it down. HID lamps will really add some heat.
NUTRIENTS:
We highly recommend the Flora Series nutrient solutions put out by GH (General Hydroponics).
This stuff is superior, easy to use, and reasonably priced. It consists of 3 parts (Flora Grow; Flora
Micro; and Flora Bloom). If you have hard water, get the Hardwater Flora Micro instead. For this
small garden, order a quart of each of the three solutions: http://www.hydroponicssimplified.com/cheap-hydroponics-supplies.html#nutrients. Stick with Flora Series, follow the
label directions, and you can't go wrong!
The growing area (and therefore nutrient bucket) should be kept cool (55-70°). This is especially
important for the cool-season crops like lettuce and broccoli. Learn more about hydroponics
nutrient solutions here: http://www.hydroponics-simplified.com/hydroponic-solution.html. We
also provide a nifty little mixing chart there for the Flora nutrients that you can print out and save.
© 2009 http://www.hydroponics-simplified.com All rights reserved. Page 4
For each 2-gallon batch of nutrient solution, add 2 tsp. of each of the 3 parts, separately. Never
mix the nutrient solutions together, only add to the water. As the plants mature, change the ratio
of the nutrient solution as directed on the bottles, or in Stella's mixing chart.
pH- It is a very good idea for any serious hydroponics project to keep the pH of the water in the
proper range, which is 5.5 to 6.5 (6.0 is ideal). If the pH is out of range, some of the nutrients get
“locked out” and the plants suffer. GH puts out a simple test kit with pH up & down solutions
cheap. It will last you through many gardens: http://www.hydroponics-simplified.com/cheaphydroponics-supplies.html#nutrients.
GROWING MEDIA:
We recommend a 50/50 Coco Coir and perlite mixture for the AutoPots. Line the bottom of the
pots first with the provided root mats. You cannot use LECA (Hydroton or clay balls) in this
system.
This is a brick of Coco-Coir, you can order one here: http://www.hydroponicssimplified.com/cheap-hydroponics-supplies.html#media
Perlite can be bought at any garden center. Coco Tek must be ordered from a hydroponics
supplier. Learn more about hydroponic growing media here: http://www.hydroponicssimplified.com/hydroponic-growing-medium.html.
© 2009 http://www.hydroponics-simplified.com All rights reserved. Page 5
EXPANDING THE SYSTEM:
This modular growing system is very easy to expand. You just buy more modules and “t” into the
irrigation tubing to provide nutrient solution to each grow tray. Of course, after about 2 modules,
it will be necessary to provide a larger reservoir for the solution. But as we said earlier, you can
create an entire greenhouse filled with nothing but Autopots... the hydroponics “no brainer”.
© 2009 http://www.hydroponics-simplified.com All rights reserved. Page 6
We hope you will try out our plans for this cool little wick hydoponics system. You will be amazed
at the size and quality of produce you can reap from this one unit. It provides a great introduction
to hydroponics for adults and children alike, and it's just plain FUN.
Our guess is that once you get a taste of hydro in this way, you will go on to bigger and better
things. This field of horticulture is wide open! There are many different methods for you to try,
and you'll just get more knowledgeable and skilled at it as time goes on.
You might try growing heirloom tomatoes, medical herbs or even orchids. Or you might just enjoy
munching on your own healthy, homegrown salad micro-greens! No matter which way your
interests take you, you are sure to enjoy this clean, healthy, prolific, earth-friendly gardening
method. We just love hydroponics and know you will too.
Visit our website: http://www.hydroponics-simplified.com often for updates on equipment,
lighting, nutrition, plants and seeds, pests, grow-closets, and plans for several other different
growing systems. We provide simple information, insider secrets, and easy-to-follow instructions
to get you up and growing in no time...
Enjoy!
Simon & Stella
Disclaimer: Many of the clickable links in this ebook are affiliate links, meaning that
if you buy through one of those links, we receive a very small commission (just about
enough to keep the website up and growing!).
Rest assured, however, that we use these products often and highly recommend
them. If you see it here, rest assured that it has our personal stamp of approval!
If you do choose to order supplies through our links, please accept our thanks for
your valued patronage.
© 2009 http://www.hydroponics-simplified.com All rights reserved. Page 7
Educational Links
Access Excellence
Access Excellence is a national educational program that provides high school biology and life science
teachers access to sources of new scientific information via the World Wide Web. This lesson plan,
"Building and Using a Hydroponic/Aquaculture System in the Classroom," is a great unit for teaching
hydroponics. Stop by and see the details!
Aeroponics International
This site has a great section called "Student and Teacher Science Projects." Stop by and get some ideas!
Bergen Academy
Students and teachers from Bergen Academy have been learning all about hydroponics and
aquaponics--even farming in space! And, lucky for you, they've posted many of their findings on their
amazing Web site. Teachers: Make sure you take a look at the many lesson plans provided for your
perusal on this site. You could spend days here . . .
Bradley Hydroponics
Learn all about hydroponic projects going on around the world, hydroponic games, nutrition, and much
more. Great resources for educators and kids alike!
Carbon Quest
Projects from all over the world--including hydroponics--are illustrated at this great Web site.
Participating organizations include NASA and the United Nations.
The Conservation Fund's Freshwater Institute
Education and Outreach explains a bit about how the Conservation Fund's Freshwater Institute has
become involved with education and aquaponics. Click on the links to see their work in action.
Foothill Hydroponics
Every educator involved with hydroponics--or even anyone who has ever thought about the
possibilities of a hydroponic unit--must stop by this site. The Foothill Hydroponics Library of
Brochures is an amazing database of information.
General Hydroponics
General Hydroponics will donate hydroponic products to schools with teachers who use hydroponics in
their classrooms or who are considering doing so.
Hawai'i Department of Education
"Simply Hydroponics"--An E-School Project--a section of the Hawai'i Department of Education Web
site--provides guidelines and general lesson plans for an entire hydroponic unit.
Homegrown Hydroponics
This hydroponic merchant has responded to the many requests they receive for science project ideas by
providing educators and students with the Science Projects page. Once you have a growing system and
are ready to go, stop by for some hints and tips.
Hydroponic University
Beginning students of hydroponics will find some great resources at this site, including tips, a forum
for asking questions, and free system plans.
Konawaena High & Intermediate School
Stop by the bizjournals.com news site and read the article, "Teacher Bets Hydroponic Projects Grow
Profits," which describes how teacher Bill Woerner got involved with hydroponics in Hawaii.
National Gardening Association
"Sowing and Growing Sans Soil", "What . . . No Soil?", "Hooked on Hydroponics"
Kidsgardening.com--sponsored by the National Gardening Association (NGA)--has tons of great ideas
to get kids growing. Take a look at these hydroponic articles written by NGA staff members and get
some ideas for your classroom. This information includes some great lesson plan material.
National Gardening Association
The electronic home of the NGA has several great resources for teachers. Take a look at their free email newsletter.
Nelson/Pade Multimedia
Here you can learn more about aquaponics--the fascinating combination of aquaculture and
hydroponics. The site features information about the Aquaponics Journal and has some resources for
educators.
The Super Hydroponic Awesome Radish Project (S.H.A.R.P.) Lesson Plans for Hydroponics
The Super Hydroponic Awesome Radish Project (S.H.A.R.P.) Lesson Plans for Hydroponics is a great
spot to bone up on the basics of hydroponics and then get down to some soilless growing. The pages
include information on how to set up a passive wicking system, suggested environmental conditions for
growing radishes, mixing the nutrient solution, and much more. S.H.A.R.P. is part of the extensive
ThinkQuest educational database.
The STELLAR Program at NASA AMES Research Center
The STELLAR Hydroponics Module features lesson plans galore for students from kindergarten all the
way through 12th grade! Bookmark this "stellar" page and regularly return to glean innovative
educational ideas.
Stratford Northwestern Secondary School
This Canadian school has a great hydroponic lab. This page features pictures, ideas, and more--stop by
and see what they've done. "The hydroponics lab is a great hands-on experience. Not only did I learn
lots, but I had fun." --L. Bell, Grade 12
The Teaching Parent Guide to Resources & Services
The Hydroponic Reference Center is an excellent, intelligent, and expansive collection of Web pages.
Browse through the seemingly endless series of interconnected pages and store these gems for use in
your own classroom or at home. Follow the tortoise!
Tunstall High School Aquaponics Project
Teachers at Tunstall High became involved with aquaponics in order to guide their students along the
cutting edge of technology as it relates to agriculture and science. Stop by and see some pictures of
their operation.
The University of Florida Cooperative Extension Service
The Grow Your Own Vegetables Without Soil page features some valuable hobbyist hydroponic
information. Learn about water vs. aggregate culture and get some recipes for nutrient solutions and
growing media.
Virginia Hydroponics Teacher Resource Center
Great resources and teaching ideas. The Basic Hydroponic Information page is loaded with vital data.
Yale-New Haven Teachers Institute--Solar Greenhouses
Learn more about solar energy and greenhouses at this site. It includes plans for how to build a model
greenhouse and classroom activities.
HYDRO JUICE
Plant nutrient is available from the hydro shop (hydroponics supplier). These
concentrated nutrient solutions are diluted in water to make the hydro juice to feed the plants.
Simple nutrient concentrates are easier and cheaper (from $8 for 750 ml.). But some of the
nutrient chemicals precipitate out as flakes before use and are lost. Two part nutrient
concentrates (from $20 for 2L.) don't have this problem. By separating nutrient chemicals they
allow more nutrients to be added same amount of water.
Mixing the two part hydro juice. Half fill the nutrient tank, mix the required amount of
concentrate Part A in the water. Fill the tank and mix required amount of concentrate Part B.
Check the instructions on the containers before buying or using either type of nutrient
concentrate.
List of the 16 elements all plants need to grow and concentrations in solution.
NAME
ELEMENT PPM
Nitrogen
N
96
Phosphorous P
48
Potassium
K
246
Calcium
Ca
123
Magnesium
Mg
48
Sulfate
SO
412
Iron
Fe
3
Manganese
Mn
0.5
Zinc
Zn
0.08
Copper
Cu
0.06
Boron
B
0.5
Molybdenum Mo
0.1
I have only used per mixed nutrient solution and am yet to try the formulation below, so if
you have any info could you please let me know about it, thanx.
The 16 elements in the table above are derived by plants from the atmosphere or from minerals in
the soil, Dr. Alan Cooper proposed this formulation for his NFT hydroponic system, a typical nutrient
solution.
The table below contains the ingredients to be added to 1000 liters of water, in practice the
solution is concentrated in to 2 parts, preventing loses from chemical reactions. Fill two 10 liter plastic
bottles with water mark that part "A" and part "B". Dissolve calcium nitrate and EDTA iron in part "A"
and the rest of the ingredients in part "B".
Concentrates are used by adding 100mls.(cc's.) of each part per 10 liters of water. The
concentration of the final solution can be measured with a EC meter (electrical conductivity meter),
this reads the conductivity of the nutrient solution.
Nutrient Chemicals
Weight in grams
Potassium dihydrogen phosphate 263.00
Potassium nitrate
583.00
Calcium nitrate
1003.00
Magnesium sulphate
513.00
EDTA iron
79.00
Manganous sulphate
6.10
Boric acid
1.70
Copper sulphate
0.39
Ammonium molybdate
0.37
Zinc sulphate
0.44
Hydroponics and the Scientific Method
Step One: Ask a Question
The first step in an experiment is to ask a question about whatever you want to find out from
hydroponics. This could be as simple as "Can I grow radish plants without soil?" For a more ambitious
experiment, you might ask a question about plant nutrition such as "How much magnesium do radish
plants need to grow?" or "How do radish plants react to concentrated nitric acid?"
For a question to be answered scientifically, it must be clear and testable, and the phenomenon that you
question must be measurable and controllable. For instance, you could not ask "Is hydroponics superior
to soil for growing plants?" because whether something is "superior" is a matter of opinion.
Step Two: Form a Hypothesis
The next step in an experiment is to come up with a hypothesis, a tentative explanation for a scientific
phenomenon. For instance, you might hypothesize:
Radish plants can grow in a nutrient solution without soil.
Magnesium is essential for normal radish plant growth.
Concentrated nitric acid is harmful to radish plants.
Make sure your hypothesis can be proven wrong. If it cannot be proven wrong, it is useless to conduct
an experiment to test it.
Along with a hypothesis comes a prediction. A prediction is what you think will happen in the
experiment. It takes the form of an if/then statement: IF the hypothesis is true, THEN these are the
results I expect.
Examples:
IF radishes can grow in a nutrient solution without soil, THEN these plants will grow.
IF magnesium is essential to radish growth, THEN radishes without magnesium in their solution will
develop chlorosis.
IF concentrated nitric acid is harmful to radish plants, THEN plants fed concentrated nitric acid will
drop dead within one hour.
Step Three: Determine Variables
There are three kinds of variables that you must account for in an experiment. The independent
variable is what you change in the experiment. For instance, if you are trying to find out how much
magnesium radish plants need to grow, your independent variable might be concentration of
magnesium in the nutrient solution. It is important that you have only one independent variable in your
experiment. For example, you cannot vary both the magnesium concentration and the temperature
conditions of your radish plants. You would not be able to draw reliable conclusions from the
experiment if you altered more than one experimental condition.
The dependent variable is what you measure in the experiment. Unlike the independent variable, an
experiment can have several dependent variables because variations in the independent variable can
have many different effects. For example, you might measure length of leaves and weight of roots to
assess the growth of radish plants. Dependent variables can include qualitative as well as quantitative
data: you might also examine the color of the radish leaves and eat the roots to see how they taste. Such
data cannot be measured but is still useful when you describe and compare it.
Any other conditions in the experiment are called controlled variables. You must keep these
conditions constant for all plants in the experiment. Controlled variables might include light exposure,
humidity, pH of solution, ambient noise, etc. If you change these variables, they become independent
variables, and remember that you cannot have more than one independent variable in a scientific
experiment.
Step Four: Design a Procedure
The procedure is the exact steps you take to carry out your experiment. This may change during the
experiment if you discover a better way to do something than your original procedure. Be sure to note
all changes in your procedure.
One important thing to include in your procedure is an appropriate level of treatment. The level of
treatment is the extent to which you change your independent variable. For example, if you are testing
the effects of magnesium concentration on radish growth, your levels of treatment might include no
magnesium (0%), normal magnesium (100%), and double magnesium (200%). Note that these values
are relative to the "normal" value, which is given in the recipe for the nutrient solution. Make sure you
note the numeric value of "normal" (i.e. concentration in moles per liter). More extreme levels of
treatment usually get more visible results, but less extreme levels of treatment usually simulate realworld conditions better.
Replication is the number of times you repeat a specific procedure. This is important to ensure that
your experimental data is reliable and less subject to chance variation. For example, in the magnesium
experiment, you might have two pots of radish plants in each nutrient solution and three plants in each
pot. This way, some plants may grow tall and others may not grow much at all, but you can compare
the general growth pattern of all the plants with the general growth pattern of the plants in the other
nutrient solutions.
The control group is the group of plants in which the independent variable is held at a "normal" level.
The purpose of a control group is to show what would normally happen and compare it with what
happens when you change the independent variable. This shows if the independent variable is really
responsible for your observations. For example, in the magnesium experiment, the control group would
be the radishes with 100% of normal magnesium concentration in their nutrient solution.
Be careful not to confuse the control group with the controlled variables. Remember, the control
group is the group in which the independent variable isn't changed, and the controlled variables are the
variables that never change in any group.
Source for entire lesson: Campbell, Neil A. "Lab Topic 1: Scientific Investigation." Lab Manual for Campbell, Fifth Edition.
Ed. Dan Wivagg. Menlo Park, California: Benjamin/Cummings, 2000, pp. 1-27.
Let it Grow and See What Happens
Step One: Maintaining the Experiment
During the course of the experiment, the nutrient solution will have to be replenished
frequently due to water evaporation. When the level of solution is low, add deionized water
until the level of solution is up to where it should be. This may seem like you are diluting
the solution, but it actually maintains the concentration of the solution at about where it
should be. The reason for this is that when water evaporates, it leaves behind any chemicals that are
dissolved in it, so the solution becomes more concentrated after evaporation. Be sure to refill all the
nutrient solution containers at the same time.
Although evaporation is the primary reason the level of nutrient solution
decreases in the container, the plants use up nutrients too. Also, algae tends
to grow in a nutrient solution that is left out for a while. Because of this,
you should replace the nutrient solution in each hydroponic apparatus
about once every two weeks or so. When you replace the nutrient solution,
first remove the pots from the hydroponic apparatus. If the felt strips are
covered with green algae, rub off as much as possible with your fingers.
We are not sure if the algae is harmful to the experiment, but it may use up
nutrients, making them unavailable to your plants, and it makes the
experiment look ugly. Place the pots in bowls of water so that the roots and
the felt do not dry out.
Remove the support boards and clean them thoroughly with soap and water. Then pour the nutrient
solution out of its container, wash the container with soap and water, and disinfect it with rubbing
alcohol or a chemical cleaner to discourage algae growth. Make new nutrient solution in the mixing
bottle according to the recipe you calculated in Lesson Three, and pour it into the nutrient solution
container. When you do this, you should also pour some through the felt and the Perlite in the pots to
feed the plants directly and encourage capillary action in the felt. When you have made enough nutrient
solution to fill the container, replace the boards and the pots the way they were before. Your hydroponic
apparatus is now ready to go again. Be sure to replace all the nutrient solutions in the entire experiment
at the same time. Note in your observations each time you do this.
You should also make sure the controlled variables are staying as consistent as possible. The most
important thing is that the controlled variables are the same for all the plants at any given time, but it is
also important that they stay within reasonable limits to keep the plants healthy. Make sure the plants
are getting about twelve hours of light (give or take a few) from the grow light or the sun. Make sure
the temperature is between 55-85° F. Make sure the relative humidity is at least 45% and ideally
between 60-75%.
Source: Casana, Maritza. [email protected]. "Práctica de producción de hortalizas bajo la técnica de hidroponía
en agua y perlita." 7 Jan 2001. Personal e-mail. (14 Jan 2001).
Step Two: Changes in the Experiment
During your experiment, the plants may grow large enough that they are overcrowding their pots and
competing with each other. When this happens, you may need to remove some plants to alleviate the
overcrowding. If you do this, be sure to remove the same number of plants from all the pots in the
experiment at the same time. Select for removal the plants that look the least healthy. Note in your
observations when you do this.
You also may need to switch to different nutrient solutions if you begin your experiment with a starter
solution for all the plants. Do this in the same way that you would replace the nutrient solutions as in
Step One, but make different nutrient solutions for each hydroponic apparatus. Be sure to mix the
correct volumes of each concentrated part as you calculated in Lesson Three. Note in your observations
when you do this.
Step Three: Handling Emergencies
If the plants are not looking healthy, here are some things to check:
• Are the strips of felt moist? If not, the nutrient solution is not coming into the pots by capillary
action. Make sure the level of nutrient solution in the container is high, and make sure the felt is
as far immersed in the solution as it will go. Also, if you are refilling the nutrient solution tub,
pour some on the felt strips to "prime" them for capillary action. If you are not making more
nutrient solution, you should do the same with deionized water.
• Are the light conditions appropriate? If the plants are getting significantly more or less than
twelve hours of light per day, you may need to adjust the lighting conditions.
• Is the air humid enough? If not, use a hoochie-coochie machine to raise the humidity or spray
water all over with a spray bottle or hose.
• Is the temperature appropriate? If things are too cold, you may need to get a heater. If things are
too hot, you may need to shade the plants, put ice in the nutrient solution, or use an air
conditioner. The temperature of the water in the hoochie-coochie machine can also influence
temperature conditions.
Spraying water with a spray bottle, though not a substitute for fixing what is wrong with the
experiment, is generally good as a temporary remedy to alleviate some of these common problems.
Step Four: Making Observations
During the experiment, you may want to measure and record data on the following dependent
variables:
• Length of plant leaves
• Color of plant leaves
• Anything unusual you observe
You also may want to take pictures of each hydroponic apparatus to document the growth of the plants
subject to different treatments.
At the end of the experiment, you may want to measure and record data on the following dependent
variables:
•
•
•
•
Length of plant leaves
Color of plant leaves
Length of plant roots
Color of plant roots
•
•
•
•
•
Weight of entire plant
Weight of edible parts (if there are edible parts)
Color of edible parts
Taste of edible parts
Anything unusual you observe
Note that you cannot make any observations on the roots of the plants during the experiment. If you
pull the plants out of the pots to observe the roots, you may break off the roots, which is bad for the
plants. This is especially true if your plant has "super roots" that grow out of the bottom of the pot and
down the strips of felt.
You should end your experiment after a predetermined number of days or after your plants are fullgrown or have developed edible parts.
Step Five: Organizing Data and Drawing Conclusions
The goal of data tables and graphs is to present data in a way that is as easy to understand as possible.
Because of this, you may not want to include all the measurements you made of every plant; rather, you
may only want to include the average measurements of the plants as well as perhaps the highest and
lowest measurements to indicate the range.
Graphs are helpful to show visually what happened in your experiment. To show progress throughout
the experiment, you may want to use a line graph of, for example, average leaf length vs. time. You
might make multiple lines on the graph to indicate the average leaf lengths for plants in different
nutrient solutions. You could show the same thing in a data table as well. Be sure to give titles to all
your data tables and graphs, and make sure the titles clearly summarize the purpose of the data table or
graph.
To show the results at the end of the experiment, a bar graph is a good choice. For example, you might
make a bar graph of average plant weight for plants growing in different nutrient solutions. The
independent variable (in this case, which nutrient solution) should be graphed on the x-axis, and the
dependent variable (in this case, average plant weight) should be graphed on the y-axis. You could
show the same thing in a data table as well.
You can then use these graphs and data tables to draw conclusions. Which nutrient solution produced
the healthiest plants in your experiment? You could conclude that the nutrient solution that produced
the healthiest plants had the closest-to-ideal concentration of the chemical that was your independent
variable. Note any sources of error in your experiment that could cause you to draw mistaken
conclusions.
Source: Campbell, Neil A. "Lab Topic 1: Scientific Investigation." Lab Manual for Campbell, Fifth Edition. Ed. Dan
Wivagg. Menlo Park, California: Benjamin/Cummings, 2000, pp. 1-27.
Focus Questions
• Why is it okay to add deionized water to your nutrient solution when it is running low?
• Why might algae be a problem in a hydroponic experiment?
• Why should you pour nutrient solution through the felt when you replenish the nutrient
solution?
• What conditions should you check if your plants do not look healthy? What can you do to
change each of these conditions?
•
•
•
•
•
•
•
What dependent variables can you measure during the experiment?
What dependent variables can you measure after the experiment is over?
Why can't you measure the plants' roots during the experiment?
How do you know when to end your experiment?
How do you summarize your data to make it easier to understand?
What is a bar graph good for showing? What is a line graph good for showing?
How can you draw conclusions based on your data tables and graphs?
Developed By:
Lisa Modee
Oregon
S
Agriculture in the
Classroom Foundation
ummer Ag Institute
Lesson Plans
Title of Lesson:
Hydroponic Plant Investigations
Academic Subject:
Science and Math
Theme:
Compare the growth rate of hydroponically grown plants to those grown in soil.
Grade Level:
4/5
CIM/CAM Standards:
. Science, 5th grade—Describe the basic plant and animal structures and their functions.
. Science, 5th grade—Ask questions and make predictions that are based on observations and can be
explored through simple investigations.
. Science, 5th grade—Design an investigation to answer questions or check predictions.
4. Science, 5th grade—Collect, organize, and summarize data from investigations.
5. Science, 5th grade—Summarize, analyze, and interpret data from an investigation.
6. Math, 5th grade—Select the appropriate units to measure length.
7. Math, 5th grade—Measure length, ….using standard and nonstandard units of measure.
8. Math, 5th grade—Collect, organize, display and analyze data using number lines, bar graphs, line graphs,
circle graphs, stem and leaf plots, and histograms.
Oregon Agriculture in the Classroom Foundation • http://AITC.oregonstate.edu
Learner Objective: (The student will)
. Identify the stages of seed germination.
. Define the related vocabulary words and identify the location and functions of the major plant parts.
. Understand the need to add nutrients to the water when growing plants hydroponically.
4. Write a scientific inquiry investigation to determine the effect that growing plants hydroponically has on
their growth rate.
5. Identify questions that can be answered by their scientific investigation and write a hypothesis.
6. Recognize reasons for controlling variables.
7. Measure and record plant growth over a period of several weeks.
8. Create a line or bar graph showing the comparison data of the hydroponically and soil grown plants’ growth
rates.
9. Draw conclusions about their hypothesis based on the data they have collected and recorded.
0. Present their graphs and conclusions to the class.
Vocabulary:
. Hydroponics—the science of growing plants without soil.
. Seed—the part of a plant that is responsible for starting a new plant.
. Root—the underground part of a plant that anchors the plant, absorbs water and minerals, and stores food.
4. Stem—the part of the plant that holds it upright supporting flowers and leaves.
5. Leaf—an extension of the stem that turns sunlight into food through a process called photosynthesis.
6. Flower—The part of the plant that is responsible for producing seeds.
7. Fruit—the fleshy part of plants that holds seeds. The fruit is responsible for protecting and scattering the
plants seeds.
8. Germinate—when a seed takes in water and begins to grow.
Oregon Agriculture in the Classroom Foundation • http://AITC.oregonstate.edu
9. Phloem—plant tissue that transports food in the plant.
0. Nutrients—substances used by plants to make their food and make plant growth possible, made up of
carbon dioxide, water and minerals.
. Hypothesis—something not proved but assumed to be true until further investigation.
Anticipatory Set:
Ask students, “What do plants need to grow?” and list their responses on the board. Ask students if they think
plants can grow without soil. Explain that we will be learning about the science of growing plants without soil
(hydroponics) and comparing them to plants grown in soil.
Instructional Outline
(Teaching Content)
Strategies
(What to do, explain or have students do)
1.
Introduce students to vocabulary.
. *Distribute vocabulary handout and read through
it together. *Have each student make a “flip
book” study guide using the definitions from the
handout. *Flip books will be used throughout the
following 1-2 weeks for independent study, partner
quizzes, and class games to help students learn their
vocabulary. *At the end of the second week an
independent vocabulary quiz will be given.
2.
Review seed germination.
. *Divide students into three groups and distribute/
read the lesson worksheet on making a living
necklace from the Oregon Agriculture in The
Classroom Foundation. *Have each group gather
their supplies from the table and complete a
necklace using a bean seed. *Students may take
turns wearing their group necklace or set it in a
window. *Necklaces will be checked in 4 or 5 days
at which time the plant parts and germination will
be discussed and then labeled on the germination
worksheet.
3.
Explain hydroponic growing set up and identify the need for, content of, and process of adding nutrients for the plants.
. *Show students the hydroponic system and discuss
its parts and their functions. *Present information
on the nutrients needed for successful hydroponic
plant growth, using the Virginia Hydroponics
article. *Inform students that we will use fertilizer
to provide complete nutrients for the plants since
they will not be getting any nutrients from soil.
Oregon Agriculture in the Classroom Foundation • http://AITC.oregonstate.edu
4.
Planting seeds.
4. Distribute seeds to each of the three groups, giving
one group lettuce seeds, the second group basic
seeds, and the third group tomato seeds. Have each
group plant 3-4 of their seeds in soil containers
and 3-4 of their seeds in their group’s section of the
hydroponic garden system.
5.
Introduce and facilitate the completion of the scientific inquiry investigation plan form.
5. *Distribute the plan forms, which students should
already be somewhat familiar with from previous
science investigations. *Complete the first two
sections together discussing the questions we
wish to answer in our investigation, the variables
we will keep the same in order to conduct a “fair”
investigation and the variables we will change.
*Have each group discuss and agree upon a
hypothesis to write on the final section of the plan
form.
6.
Plant care.
7.
Data collection and recording.
8.
Plant measurement and data collection.
9.
Display data in a graph.
6. After insuring that the only differences in the
growing circumstances of the plants is soil vs.
hydroponic system, have each group assist in the
care of, and watch for progress in their plants’
growth.
7. *During this period of waiting for plant growth use
lessons from the math text to practice collecting,
recording, graphing and interpreting data. *Also
have students practice making accurate length
measurements on various objects in inches and
centimeters.
8. As plants begin to show above soil level have groups
choose the one healthiest of each of their soil
and hydroponic plants to use for data collection.
*Explain that these two plants for each group
will be the same plants they measure each time in
order to be collecting reliable data. *Have each
group measure their two plants and record the
measurements and date, and label with soil and
hydroponic in their science notebooks. *These
measurements and recordings will continue twice a
week over the next several weeks.
9. Have each group create a poster size line or bar
graph to show their comparison data on the rate of
growth for their soil grown vs. hydroponically grown
plants.
Oregon Agriculture in the Classroom Foundation • http://AITC.oregonstate.edu
10.
Evaluate hypothesis.
11.
Group presentations.
0. *Have each group use their data and graph
to discuss and evaluate the accuracy of their
original hypothesis concerning the soil grown vs.
hydroponically grown plants. *Have each student
put his/her conclusions in writing on the final page
of their investigation plan forms.
. Have each group plan, practice and present their
original hypothesis, graph and conclusions to the
class.
Extensions:
Read about and discuss the possible benefits of and uses of hydroponic farming in U.S. agriculture. This could
even piggy-back into a research assignment or creative writing project related to hydroponic farming.
Closure:
*Display group graphs and conclusions.
*As a class determine which of the plant types showed the greatest differences in growth.
*If possible, take a field trip to the Davis Farm in Corvallis to see a hydroponic operation first hand.
Resources:
. Growing Edge Web Site: http://www.growingedge.com/basics/start.html
. “Grow Your Own Vegetables Without Soil 1; University of Florida Extension article.
. Virginia Hydroponics: http://www.hydro4u.com/resource_center/faq.htm
4. “History of Hydroponics”: http://archimedes.galilei.com/raiar/histhydr.htm
5. Davis Farm, Corvallis OR
6. “Living Necklace” lesson from Oregon Agriculture in the Classroom Foundation
7. “Seeds Stems And Such” lesson from Oregon 4-Hagriculture in the Classroom Curriculum Handbook for
Grades 4-5, 2003
8. Hydroponic kit from SAI
9. Hydroponic supplies from: www.americanag.com
0. kidsgardening.com
Oregon Agriculture in the Classroom Foundation • http://AITC.oregonstate.edu
Evaluation:
. Evaluate student notebooks for accuracy in recording plant measurements and growth records.
. Evaluate student made comparison graphs of plant growth data.
. Evaluate student science inquiry packets for their accuracy and completeness using the state scoring guide.
4. Evaluate student accuracy on vocabulary and plant part quiz.
Oregon Agriculture in the Classroom Foundation • http://AITC.oregonstate.edu
Dedicated to: Education • Research • Fun!
Hydroponic orchids
on the increase!
Monterey County, California, grew and
shipped 12.5 million dollars worth of
orchids in 1998.
The final totals are not yet in for the
year 2000, but it could exceed 25 million
dollars!
Andy Matus is the largest California
orchid grower and has found cultural
methods to ensure that blooming orchids
are available 12 months out of the year.
Hydroponics and tissue culture methods
are combined with intensive breeding to
create new hybrids that have the
outstanding characteristics of small plants
with huge, long-lasting blossoms.
Source: Growing Edge magazine Volume 12
#3 January/February 2001, pages 54-55
Hydromax 2000
aeroponic system
The photo at right shows healthy white
roots when the top cover is lifted. The
lower parts of the roots dangle into the pool
of nutrient solution. The upper roots are
constantly sprayed with nutrient water by a
submersible pump.
The special nozzles break the water into a
flat circular pattern of droplets. These
droplets fly through the air and become
charged with dissolved oxygen on their way
to the plant roots.
Issue #12 • Spring 2001
Lights! Hydroponics!
Twentieth Century Fox Film Corporation
purchased many of the newest HID
Horticultural lighting systems, as well as
complete Hydroponic growing systems
and living Hydroponic plants, for an
upcoming movie that will be set about 50
years in the future.
Some of our advanced Hydromax
Aeroponic systems are also being used as
props for the project.
LAUSD orders more Xtra-Edge Hydroponic
nutrients
San Miguel High
School, in South Gate,
ordered Oasis
propagation blocks and
Xtra-Edge
Hydroponic nutrients
as part of its new
science education
program.
Mount Vernon
Middle School, in Los
Angeles, ordered
special full-spectrum
horticultural lights for the part of its new
science education program that uses
Hydroponics as a learning tool.
“w
The photo above shows our resident hels.nabortiydpcf-m
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several hundred small seedlings, making it
possible to share one Hydroponic
Laboratory with more than one classroom.
The special garden carts have two tiers
of full-spectrum lighting, with four 48-inch
fluorescent tubes on each tier.
This size cart is capable of supporting
Hydromax Mini Ebb & Flow/NFT Hydroponic system
This photo
shows lettuce
growing in 3inch rockwool
cubes.
A very small
submersible
pump raises
water from the
lower reservoir
to the growing
tray.
The growing tray fits inside the reservoir, making a small self
contained system. The water drains by gravity back to the lower
tank.
Our New Hobby
by Ken Suarez
My wife Robin and I had been interested
in Hydroponics for years, so when our
son, Paul, asked us to help him put
together a small Hydroponic garden for
his middle-school science fair, we were
ready to try it.
We helped him design the little garden
and went to Foothill Hydroponics, where
Mr. Mohsen Daha was very
helpful to Paul. He gave Paul
technical advice, lots of
literature, and was generous
with discount prices.
Paul’s tiny garden, made from
a recycled soap tub, was a great
success. But after the fair, its
four tiny one-inch rockwool pots
couldn’t contain the tomato and
pepper plants to maturity, so we
let the project go and put the
empty tub in the garage, where
it sat for over a year.
But our interest persisted, and
this year we decided to
experiment with a slightly larger
setup. After much
consideration, we decided on a
Hydromax 2000 ebb and flow
system, which holds twelve
plants. Since it’s indoors, we
light it with a 250-watt metal
halide lamp.
Setting up the system was
easy. Foothill Hydroponics staff explained
everything and were available by phone
for further help.
By using starter plant sets already in
four-inch rock wool containers, we were
able to have an “instant” indoor salad
farm, which is approximately two feet
wide by four feet long, in which we are
growing tomatoes, lettuce, green peppers,
chives, and flowers. This will provide us
with fresh salads and flowers during the
winter months.
We will use Paul’s tiny science project
farm to start plants from seeds and move
them to the Hydromax when they’re
ready to transplant.
The whole family is enjoying the new
hobby. Besides providing food and
beauty, the plants add oxygen to the air,
and there have been several, unexpected
bonuses. The metal halide lamp in our
big family room cheers us up on cold, wet,
gloomy days. It makes our family room
such a cheerful place to be in, that we
wish we had bought a metal halide lamp
years ago, even if we didn’t intend to
grow hydroponic vegetables. Paul says
that the light is great for drawing and
drafting for school projects because he can
see fine detail with it much better than
with the regular house lights. Our
pre-existing indoor plants, growing in
soil, get the double benefit of the
“indoor sunlight” and the recycled
nutrient solution.
The nutrient solution recirculating
ads moisture to the air and sounds like
we have a small waterfall in the house.
So, if you’re looking for a new
hobby, starting a Hydroponic garden
is fun, it’s educational, it will provide
you with vegetables and flowers, and it
will cheer you up on cold winter days.
Past newsletters
available Online! at www.foothillhydroponics.com
Foothill Hydroponics supports Symposium
On November 18, 2000, the Los
Angeles County Office of Education
hosted a “New Teacher Fall
Symposium,” for new math and
science teachers, at the Sheraton
Hotel in Cerritos, California.
Foothill Hydroponics participated
by displaying hydroponic supplies and
by highlighting the new aeroponic
spray system in a booth.
Foothill Hydroponics also presented
a breakout session titled
“Hydroponics in the Classroom.”
The workshop, presented by Pat
Brown and Ginger Krelle,
demonstrated easy and
inexpensive ways for
teachers to energize their
curricula, while meeting
California science
standards, by growing
plants in the classroom
hydroponically.
Teachers also learned how
to utilize Hydroponics to
create en environment
which fosters hands-on learning and allows
students to use the scientific method to
perform their own experiments.
Teachers who attended the session were
inspired, and Dean C. Gilbert, the L.A.
County Science Consultant, stated that “the
workshop received very positive comments,
disseminated a great deal of information, and
made a definite impact on these teachers.”
The workshop was well-attended, and all
participants received starter kits provided by
Foothill Hydroponics.
An aeroponic starter kit was raffled off at
the end of the session, and was eagerly
received by a 7th-grade science teacher.
My Hydroponic
Greenhouse
By Cal Singman
The greenhouse that I built was based on
the location and size that suited my need.
Since I had no room in my backyard, the
only available site was my driveway.
Searching for suitable plans, I chose one
in the “Popular Science Woodworking
Projects” of 1987. The plans called for an
8’ x 10’ greenhouse. I decreased the size to
8’ x 8’.
I also used 2” x 4” redwood for the
mudsill, and screws instead of nails. This
way the greenhouse can be dismantled and
moved if necessary.
The 8’ x 8’ size is a perfect size to have
two 26-gallon capacity reservoirs, one on
each side, each holding two HydroTrays or
any combination to fit.
As for the growing media, I have tried
pea gravel but have found that using the 4”
x 4” x 3” rockwool cube best suited my
needs.
I have been growing all types of lettuce,
tomatoes, sugar peas, Japanese cucumbers,
peppers and a variety of herbs.
When my crop is ripe, my wife enjoys
picking the fresh vegetables every day for
our nightly salads. This is a wonderful
fulfilling hobby and also great fun!
“Thank you,
Foothill Hydroponics,
for helping me!”
Gardening Resources, Cornell University
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Gardening resources > Houseplants > Horizontal hydroponic unit plans
Horizontal hydroponic unit plans
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page:
General Information
Tools You Will Need
Materials You Will
Need
Assembly
Jim Grefig, a Master Gardener involved
with the School Gardening Mentor
Program in Westchester County,
coupled a PVC grow-light stand with a
horizontal hydroponic system (pictured
left) from the Cornell Cooperative
Extension publication Grow with the
Flow.
Below is an excerpt from the
publication detailing how to build the
unit.
Click for larger view
Photos courtesy Jim Grefig
General Information
The horizontal hydroponic unit (Figure 1) is constructed of 1 1/2inch PVC pipe connectors, 1 1/2-inch PVC fittings (T sections and
90° elbows), 1/2-inch ABS feed line, spaghetti (feed) tubing, and
emitters.
Adding the feed line
and feed tubes
Preparing the
catchment tank
Printer-friendly .pdf file
Excerpted and adapted from
Grow with the Flow, by
Philson A.A. Warner,
Donald A. Rakow and
Charles Mazza. David
Hillman, Robert McBride
and Wayne Torgenson
helped write this section.
Figure 1 (click for larger view)
The T sections and two 90° elbows are connected with short lengths
of PVC pipe to construct a U-shaped unit that lies horizontally on a
surface. The openings of each T section (a) are positioned vertically
(upward) to become the grow ports in which plants will be set to
grow.
Two 90° elbows (b) attached to each end of the U-shaped unit and
positioned vertically (downward) connect the unit to a catchment
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tank. The feed line (c) is fastened to one leg of the U-shaped unit.
Spaghetti tubes (d) run from the feed line to the grow ports.
The unit is suspended from a simple plant light stand (e) using light
chain and S hooks and attached to a pump (t), which sits on the
covered catchment tank (g). [Note: Grefig's variation uses a light
stand constructed from PVC pipe.] Liquid is pumped from the
catchment tank through the feed line and feeder tubes to each
plant. Liquid returns through the unit to the tank by gravity.
Before beginning, read all the directions thoroughly to
understand fully the construction approach.
Tools You Will Need
●
●
●
●
●
●
●
a miter box, to make straight cuts
a hack saw, with a 24- or 32-teeth-per-inch blade
a pen or utility knife
a commercial hole punch, a #20 nail, or an ice pick
an electric drill with a 3/8-inch bit
two 3-inch or 4-inch C-clamps
a ruler or a tape measure
Materials You Will Need
For U-shaped unit:
●
●
●
●
a 75-inch length of 1 l/2-inch PVC pipe, cut to the following
dimensions:
❍ one 9-inch connector
❍ one 3-inch connector
❍ one 2 l/2-inch connector
❍ ten 6-inch connectors
the following 1 1/2-inch PVC fittings:
❍ ten T sections
❍ four 90° elbows
one small can of PVC pipe cleaner
one small can of PVC solvent-cement
For feed line and pumping system:
●
●
●
●
●
6 feet of 1/2-inch ABS pipe
fine sandpaper (120 to 150 grit)
ten barb connectors (small plastic fittings to connect the
spaghetti feed tubes to the ABS pipe)
ten 18-inch lengths of spaghetti tubing
one 5/8-inch x 1 l/2-inch bolt or dowel (to plug one end of
the ABS feed line)
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●
●
●
●
●
●
●
one tube of general purpose silicone glue and seal
one mini hose clamp (to fasten bolt or dowel in place)
one roll of electrical tape
twenty l/2-gallon-per-hour emitters (ten for unit assembly
and ten for future replacement)
ten plastic stabilizer pegs or paper clips
one catchment tank -- 16 inches long, ll inches wide, 7 inches
deep -- with cover (Rubbermaid Rough Tote Keeper, 3 gallon,
model no, 2213, or equivalent)
one pump, rated 200 gallons per hour, preferably
nonsubmersible, such as a fish tank pump (Supreme
Aquamaster Power Filter Pump, model PLSW, or equivalent)
To attach unit to the plant light stand:
●
●
●
four 18-inch lengths of light chain
eight 1/2-inch S hooks
two 3/8-inch x 2-inch threaded eye bolts, each with 2 nuts
and 2 flat washers
Assembly
1. Cut the 75-inch length of PVC pipe into the lengths specified
in the list of materials as follows:
Fasten the miter box to the work surface with a C-clamp.
Using a second C-clamp, secure the PVC pipe in the miter box
to ensure a square cut. Using the hack saw and the 90°
cutting guides on the miter box, cut all connectors and
lengths to the dimensions specified.
Other cutting methods may be employed. Miter boxes with
attached tubular saws that have replaceable blades can be
used if a fine-tooth blade (like that of a hack saw) can be
obtained. Powers saws, such as a radial arm saw, should be
used only by adults knowledgeable in tool operation and
blade selection.
Once cutting is complete, carefully use a pen knife to remove
burrs on the inside and outside edges of the cut pipe.
2. Referring to Figure 2, lay out the elbows, T sections, and PVC
pipe connectors on a flat surface.
Figure 2 (click for larger view)
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3. Assemble the unit without cement to make sure all the parts
fit correctly and to establish the proper orientation of all the
fittings. When inserting a connector into a fitting, the
connector should fit inside about onethird to halfway.
Note: Be sure that the openings of the T sections are
perfectly upright; these will be the grow ports for the plants.
The two elbow fittings that attach the ends of the U-shaped
unit to the catchment tank must be oriented downward.
4. When the unit is assembled without cement and all the
fittings are properly oriented, draw alignment marks on the
pipe connector pieces and their adjoining fittings and number
(or letter) each fitting and pipe connector joint. These marks
will ensure the proper placement and realignment of all
components when the unit is reassembled with PVC solventcement.
5. Disassemble the unit, then begin to reassemble it
permanently using the PVC pipe cleaner and PVC solventcement as follows:
a. Work on one joint at a time. You'll need to work
quickly, as PVC solvent-cement sets in about 30
seconds.
b. Apply PVC pipe cleaner to the outside surface of the
pipe connector and the inside surface of the fitting.
Allow the surfaces to dry.
c. Apply PVC solvent-cement to the outside surface of the
pipe connector and the inside surface of the fitting.
With the alignment marks on the pipe connector and
the fitting oriented 90° apart, insert the connector into
the fitting until it is snug (as in assembling the joints
without cement), simultaneously twisting the pipe 90°
until the two alignment marks match. Do this quickly,
as you have only about 30 seconds before the solventcement sets.
6. When the unit has been permanently cemented together,
allow the PVC solvent?cement to cure for about 3 hours.
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Note: Caution must be exercised when working with PVC
pipe cleaner and PVC solvent-cement. Wear eye
protection and appropriate clothing to prevent contact
with eyes and skin. These chemicals are volatile and
noxious and must be used in a well-ventilated area.
Return the covers/applicators of these substances to their
respective containers and seal them after each use to keep
fumes to a minimum. Read and observe all
manufacturer's warnings and directions for use.
Adding the feed line and feed tubes
1. Place the U-shaped unit on a flat surface in its proper
horizontal position. Place the 1/2-inch ABS feed line parallel
to one side of the hydroponic unit (Figure 3) so that one end
of the feed line is even with the base of the U and the other
extends beyond the two open ends of the unit.
Figure 3 (click for larger view)
2. Mark the feed line at intervals that align with the grow ports
in the unit. These locations are where the barb connectors
(and then the spaghetti feed tubes) will be inserted. It is not
critical to measure the intervals exactly -- the flexibility of the
spaghetti feed tubes allows for a great deal of tolerance
(Figure 4).
Figure 4 (click for larger view)
3. Lay the ABS feed line on a solid, flat surface. Using either a
commercial hole punch, a #20 nail, or an ice pick, puncture
holes at the locations marked on the pipe. (Do not drill holes.
A rough, punctured hole holds the barb connector more firmly
in place.) Using fine sandpaper, sand and clean the area
around each hole. This will ensure proper bonding and sealing
with silicone glue in later steps.
4. Insert a barb connector into each hole and attach an 18-inch
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length of spaghetti tube to each barb connector.
5. Plug the end of the ABS feed line that is aligned with the base
of the U-shaped unit with the 5/8-inch bolt or dowel. To
ensure a watertight seal, apply a coating of the silicone glue
and seal around the bolt or dowel, insert it into the end of the
pipe, and clamp it in place using the mini hose clamp.
Note: To ensure a proper seal, be sure to use a silicone glue
and seal product, not just silicone.
6. Attach the ABS feed line to the outside of the U-shaped unit
using electrical tape at several locations.
7. Seal each barb connector using the silicone glue and seal. (To
ensure a proper seal, be sure to use a silicone glue and seal
product, not just silicone.) Allow the glue and seal to cure for
24 hours.
8. After the glue and seal has cured, trim each spaghetti tube to
an appropriate length to reach a grow port. Attach an emitter
to the end of each tube.
Note: Do not cut the tubes too short. As the unit is
maintained throughout the growing cycle, it will be
necessary to remove and replace the emitters. The ends of
the tubes will become stretched, making it necessary to trim
the tubes.
9. Use a plastic stabilizer peg or a clip fashioned from a paper
clip to hold each emitter in place. Secure the peg or clip to
the spaghetti tube just above the emitter and insert it into
the rock wool plug in the grow port.
10. Attach the completed unit to the plant light stand using the
light chain and S-hooks. See Low-Cost Grow-Light Frame
Plans.
Preparing the catchment tank
1. Your catchment tank should hold approximately 3 gallons. (A
Rubbermaid Rough Tote Keeper works well. It also comes
with a cover, which supports the pump and reduces
evaporation. If the container available does not have a cover,
you can construct one from 1/4-inch plywood.)
2. Place the catchment tank at the open ends of the U-shaped
unit (where the elbow fittings point vertically downward for
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drainage) outside the upright of the plant light stand.
3. Position the elbow fittings on top of the catchment tank cover
and trace around each fitting. Remove the tank cover and
carefully cut along the traced lines using a utility knife,
creating two holes for the elbow outlets. Place the tank and
cover in place so that the elbow fittings fit through the cover.
4. With the catchment tank in place, align the open end of the
ABS feed line so it extends over the tank cover. At the
outside edge of the cover aligned with the feed line, trace a 2
1/2-inch hole. This opening will accommodate the intake of
the pump, which will sit on the tank cover. Remove the tank
cover and carefully cut along the traced line using a utility
knife.
Note: The placement and size of the hole in the catchment
tank cover may vary depending on the size and
configuration of the pump used. If a submersible pump is
used, the hole in the cover will need to be just large enough
for the ABS feed line to connect to the pump outlet. A 3gallon catchment tank, however, will accommodate only a
very small submersible pump.
5. Replace the tank cover and insert the pump intake through
the cover. Trim the end of the ABS feed line so it fits into the
pump outlet. Connect the pump to the feed line. If a straight
connection is not possible, use a short length of flexible
tubing and two mini clamps to complete the connection.
Last updated 09/18/2006 13:41:40
© Copyright, Department of Horticulture, Cornell University.
Website design: Craig Cramer [email protected]
Mention of trade names and commercial products is for educational purposes; no
discrimination is intended and no endorsement by Cornell Cooperative Extension or Cornell
University is implied. Pesticide recommendations are for informational purposes only and
manufacturers' recommendations change. Read the manufacturers' instructions carefully
before use. Cornell Cooperative Extension and Cornell University assumes no responsibility
for the use of any pesticide or chemicals. Some of the links provided are not maintained by
Cornell Cooperative Extension and Cornell University. Cornell Cooperative Extension and
Cornell University are not responsible for information on these websites. They are included
for information purposes only and no endorsement by Cornell Cooperative Extension or
Cornell University is implied. Cornell Cooperative Extension provides equal program and
employment opportunities.
http://www.gardening.cornell.edu/factsheets/growflow/index.html (7 of 7)4/10/2008 3:37:30 PM
Introduction to Hydroponics
Hydroponics is the growing of plants in water instead of soil. To do this successfully, the water must be
enriched with nutrients and sometimes oxygenated. Also, the plants must be placed in some type of
inert medium like sand or Perlite (like we used) to anchor the roots.
Hydroponics has been around for over 70 years. One of the first scientists to experiment with
hydroponic culture was Jean Boussingault, who grew plants in containers with sand and coal, feeding
them with chemical solutions of known makeup. Around the beginning of the 1930's, Professor W. F.
Gericke saw commercial potential in Boussingault's techniques and began to use them to grow
vegetables, flowers, and other types of plants. Since then, hydroponically grown vegetables have been
very important in America's history. For example, in 1939 the American army and British Air Force
installed hydroponic units in their military bases, and Allied troops ate hydroponically grown
vegetables during World War II.
Scientists can use hydroponics to test how different nutrients affect a plant. With hydroponics, a
scientist can measure exactly how much nutrient the plant is getting and can give the plant a deficiency
or overabundance of a certain macro or micronutrient and determine precisely how it affects the plant's
growth.
Hydroponics can be very important to farmers and gardeners who want complete control over their
plants. Many factors can affect plants that are grown in soil out in the fields. For a plant to receive a
well balanced diet, everything in the soil must be in perfect balance. Rarely, if ever, can you find such
ideal conditions in soil due to contamination and biological imbalances. But with hydroponics, water is
enriched with these very same nutrient salts, creating a hydroponic nutrient solution that is perfectly
balanced. And since this hydroponic nutrient solution is contained, it does not harm our environment as
does runoff from fertilized soil. Also, very little water is lost to evaporation in a hydroponic system,
making hydroponics very useful in drought stricken areas. Additionally, plants can be grown
hydroponically inside greenhouses to protect them from pests; this makes harmful pesticides
unnecessary.
Even if you are neither a scientist nor a gardener, hydroponics can be important to you. There are so
many benefits to hydroponics that it will probably become the agriculture of the future. Each day, more
facts are learned about this type of farming, and soon we will know enough to make it the most
efficient and effective way to grow plants. You, too, can benefit from the knowledge of hydroponics
and could even start an amateur flower garden or vegetable garden.
Mix the Nutrient Solution
Step One: What nutrients do plants need?
All plants require certain chemical elements to live. These elements are known as essential nutrients,
and they are divided into two categories: macronutrients, or nutrients plants need in large amounts; and
micronutrients; nutrients plants need in small amounts. Macronutrients include carbon, hydrogen,
oxygen, sulfur, phosphorus, nitrogen, potassium, calcium, and magnesium. Micronutrients include iron,
copper, zinc, nickel, manganese, molybdenum, boron, and chlorine. These elements are used by plants
in building biological molecules, as cofactors in enzymatic reactions, and in many other ways.
Plants obtain carbon and oxygen via the stomata in their leaves. However, they must absorb the other
nutrients through their roots. This is where the hydroponic nutrient solution comes in: it supplies the
plant with the nutrients it needs in the proper amounts.
Sources:
Campbell, Neil A., Jane B. Reece, and Lawrence G. Mitchell. "Plant Nutrition." Biology, Fifth Edition. Menlo Park,
California: Benjamin/Cummings, 1999, pp. 714-717.
Poli, Dorothy Belle. "BSCI 442: Plant Physiology Lecture Outlines, Fall 99."
http://www.life.umd.edu/classroom/BSCI442/lec6.html. Last visited: August, 2001.
Step Two: Figure out how much to make
One way to make a nutrient solution for hydroponics is to use the recipe proposed by Dr. Alan Cooper
for a typical hydroponic system. This recipe makes 1000 liters of solution and consists of two parts
concentrated in 10-Liter bottles. 10-Liter bottles may be hard to find, but you can alter the recipe to fit
in 2-Liter soda bottles by dividing all the ingredients by five. Since this uses one-fifth the chemicals of
the original, it only makes 200 L of solution. This may be more solution than you need. To figure out
how much solution you need, multiply the number of plants you are going to grow by the number of
days over which you are going to grow them. For example:
18 plants x 60 days = 1080 plant-days
Once you have the number of plant-days, divide 200 L by that amount to find liters of solution per
plant per day:
200 L / 1080 plant-days = 0.185 L/plant/day = 185 mL/plant/day
While this may not seem like a lot, it is probably more than the plants need. It is hard to say how
quickly plants actually use nutrients since the solution usually disappears from evaporation, but it is
reasonable to expect that the plants use very little, especially if they are small plants. At this point you
must make an educated guess based on the size of the plants. For instance, you might guess that radish
plants will use no more than about 100 mL of solution per day. Accordingly, you would divide all the
chemicals in the recipe by two in order to make about 92.6 mL/plant/day. It is not necessary to make
exactly 100 mL since you guessed at that amount anyway.
The original mixing directions call for 100 mL of each of the two concentrated parts to be added for
each 10 L of water. As with the concentrated chemicals, you can alter the mixing directions so the
entire mixture fits in a 2-Liter bottle by dividing all the amounts by five. You would then use 20 mL of
each concentrated part for each 2-Liter bottle of water. Note that if you scale the recipe for the
concentrated solution to avoid making too much, you must scale the mixing directions accordingly. For
example, since you used half as much chemical in the above example to make solution that is half as
concentrated, you must use double the volume of each concentrated part per 2-Liter bottle of water so
that the final concentration of nutrients is the same. In this example, you would use 40 mL of each part
for each 2-Liter bottle of water.
Since the volume of each concentrated part used (40 mL) is of a much lesser magnitude than the
volume of the water used (2 L = 2000 mL), one can make things easier by using 40 mL of each
concentrated part and adding enough water to make 2 L of solution instead of adding 40 mL of each
part to 2 L of water. Though this slightly alters the final concentration of the nutrient solution, it makes
the entire mixture fit into a 2-Liter bottle, and the error is tolerable because this is not an exact science
anyway.
For an experiment that involves changes in nutrient concentration, you will need to make more than
one bottle of the concentrated part that contains the chemical that is your independent variable. To
avoid wasting chemicals, you should recalculate the amount of chemical needed in each bottle if you
are using the different solutions for different lengths of time or different numbers of plants. For
example, if you make three bottles with different concentrations of magnesium sulfate and one bottle of
EDTA iron and calcium nitrate for all the plants in your experiment, you will need one-third the amount
of chemicals that you would otherwise need in each of the three bottles, but you will need the same
amount of EDTA iron and calcium nitrate that you would otherwise need. It may be good to put some
solutions in 1-Liter bottles if you don't need as much; be sure to calculate the correct volumes of those
solutions to mix.
Source: "Hydro Juice." http://members.tripod.com/~busiweb/hydro/juice.htm. Last visited: August, 2001.
Step Three: Mixing the Chemicals
Materials needed:
all chemicals listed in recipe above
balance
filter paper or container to hold chemicals while measuring
two or more 2-Liter soda bottles, or other bottles with the recipe adjusted appropriately
chemical scoop
deionized water
small funnel
If you have all the chemicals in the recipe at hand in your chemistry lab, you should mix the
concentrated solution in two parts: one with the calcium nitrate and EDTA iron, and one with all the
rest of the chemicals.
Source: "Hydro Juice." http://members.tripod.com/~busiweb/hydro/juice.htm. Last visited: August, 2001.
Measure out the amount of each chemical you need on a balance with filter paper or a container to hold
the chemicals, and mix the chemicals in clean 2-Liter soda bottles partially filled with deionized water.
Be sure to use deionized water; tap water often contains ions that can mess up your solutions. You may
need to use a small funnel to get the chemicals into the bottles without spilling them. Fill the bottles to
the top with deionized water when all the chemicals have been added.
However, if you are missing any of the chemicals, you may have to make them yourself by reacting
other chemicals. In that case it may be more practical to divide the concentrated solution into more than
two parts.
Acid-Base Reactions
Use these directions to make some of the simpler compounds in the nutrient solution recipe using acids
and bases.
EDTA Iron
Use these directions to make EDTA iron. EDTA iron is expensive to buy, but this recipe you can cook
up in a chemistry lab seems to work pretty well. Do not try to substitute a simple iron compound in
place of the EDTA iron. If you put a simple iron compound such as iron nitrate in your solution, it will
form a precipitate with other chemicals in the solution such as phosphate. To avoid this, you must use
chelated iron. A chelating agent is a molecule that grabs onto an ion such as iron and holds it tightly so
that it cannot precipitate. However, plants still have ways of extracting the iron they need from these
compounds. EDTA iron is one type of chelated iron that you can use in a nutrient solution.
Mixing Directions
Materials needed:
2-Liter clean empty mixing bottle
small funnel
graduated cylinder
Use the volume that you calculated before for each bottle of concentrated solution. Measure that
volume of solution into the graduated cylinder using the funnel, and pour it into the mixing bottle,
again using the funnel. Do this for each bottle in your recipe, and fill the mixing bottle to the top with
deionized water when you are done. Again, be sure to use deionized water so that you do not introduce
more chemicals into your nutrient solution. You now have a bottle of nutrient solution that is ready to
feed to your plants!
Focus Questions
• What essential nutrients do plants need to live?
• What are macronutrients and micronutrients? Which essential nutrients are macro? Which are
micro?
• How do plants obtain their nutrients?
• How do you figure out how much nutrient solution you need? How do you scale your recipe
accordingly?
• When you scale down the concentration of your nutrient solution, what must you do with the
volume of nutrient solution you mix?
• Why must you always use deionized water when you are mixing chemicals? What is wrong
with tap water?
• Why must you use EDTA iron in your nutrient solution? Why won't a simple iron compound
work?
SOURCEBOOK MODULE
TECHNOLOGY
Upper Primary/Lower Secondary
Designing a hydroponic system
Strand
Organiser
Level
1
2
3
4
5
6
B6
Investigation
Technology
Practice
Ideation
Production
Evaluation
Information
Materials
Nature
Techniques
Nature
Techniques
Nature
Systems
Techniques
Purpose
The activities in this module are planned to provide students with opportunities to understand
hydroponic and traditional methods of growing plants. As a class, they grow tomatoes and
strawberries using both traditional and hydroponic methods.
Overview
The following table shows the activities in this module and the way in which these are organised
into introductory, developmental and culminating phases.
Introductory
Developmental
Culminating
Brainstorm ‘What we know’
and ‘What we need to
know’.
Select a patch of ground for growing
the crops.
Brainstorm ways to measure the
success of the project.
Work out how much space is needed.
Use research activities to
find information on growing
strawberries and tomatoes.
Design a top-view to-scale plan of the
patch.
Collect information about the
strawberries and tomatoes.
Observe and record information about
the growth of the plants.
Find a local hydronponic
farmer and visit their farm.
Invite an expert from a local farm and
an irrigation company to offer advice
about the designs.
Brainstorm a list of the
materials that will be
needed.
Construct the irrigation system and
plant the crops.
Compare traditional and hydroponic
systems of agriculture.
Plan and implement ways to control
diseases and pests.
Design a survey to determine what
worked well and what could be
improved.
Design a system for monitoring and
maintaining the patch.
© The State of Queensland (The Office of the Queensland Studies Authority) 2003
Devise a system to assess the quality
of the crops.
Make inferences and
recommendations.
1
Technology
Designing a hydroponic system
Core learning outcomes
This module focuses on the following core learning outcomes from the Years 1 to 10 Technology
Syllabus:
Technology
Practice
TP 3.1 Students examine knowledge, ideas and data from a range of sources and establish the
relevance of this information when meeting design challenges.
TP 3.2 Students collaboratively generate design ideas and communicate these using
presentations, models and technical terms.
TP 3.3 Students cooperatively develop and follow production procedures to make products that
reflect their design ideas.
TP 3.4 Students test and judge how effectively their own and others’ processes and products
meet the design challenge.
Information
INF 3.1 Students describe advantages and disadvantages of different sources and forms of
information.
INF 3.2 Students select and use techniques for generating, modifying and presenting
information for different purposes.
Materials
MAT 3.1 Students choose materials according to various characteristics that best suit the
product and user.
MAT 3.2 Students select and use suitable equipment and techniques to combine materials
accurately in order to meet design requirements.
Systems
SYS 3.1 Students identify and describe relationships between inputs, processes and outputs in
systems.
SYS 3.2 Students assemble and trial systems they design by considering inputs, processes and
outputs.
Core content
The core learning outcomes are the focus for planning learning activities and assessment
tasks. Students will engage with core content (see pp. 37-40 of the syllabus) when they are
provided with opportunities to demonstrate core learning outcomes. While the content is
listed in strands for organisational convenience, no one part of that content is to be viewed
as discretely associated with a single strand.
The organisation of content within a strand should not be considered hierarchical. Any of the
content can be addressed at any appropriate level; not all of the content need be addressed
at every level. Core content should be selected to suit students' needs, interests and abilities
and to take account of their prior knowledge and experiences.
The core content should be studied in a range of contexts. These could include personal and
global contexts, as well as contexts of agriculture, business, communities, home and family,
industry, leisure and recreation, and school.
Using this module
The activities in this module are designed to provide opportunities for students to demonstrate
Level 3 learning outcomes from the Technology Practice, Materials and Systems strands. These
activities can also provide opportunities for students to develop and demonstrate the related
learning outcomes at other levels. In order to do this, teachers will need to develop additional sets
of anticipated evidence derived from the related learning outcomes at different levels. They may
also need to modify aspects of the activities.
This module includes a variety of sequenced activities requiring varying amounts of time.
Teachers can modify the design brief and related activities depending on the local contexts,
particular needs and prior knowledge of students and the availability of materials and resources.
The project needs to be started at the beginning of the year due to growing conditions for
strawberries. Cost, depending upon support from the local community, is likely to range from
$500 to $1000.
This activity is designed around growing 100 strawberries and 20 tomato plants traditionally and
100 strawberries and 20 tomato plants hydroponically.
2
© The State of Queensland (The Office of the Queensland Studies Authority) 2003
Technology
Designing a hydroponic system
Advice to teachers
This module could provide:
• opportunities for community involvement and support
• opportunities for the integrated use of computers for research (Internet), graphing and
multimedia presentations.
Resources
Students’ creativity in demonstrating core learning outcomes in this module should not be limited
by the range and scope of resources and equipment provided by the teacher. A variety of
resources should be collected over time and should be safely stored and made available to
students as required.
A variety of materials and equipment are needed in this module. Most of the materials will be
supplied if a prefabricated hydroponic kit is used. If you are making your own system, its
construction will need to be investigated. Equipment for construction of the system may vary, but
a supply of gardening and building equipment is recommended.
Evaluation of a unit of work
After completion of a unit or units of work developed from this module, teachers collect
information and make judgments about:
• teaching strategies and activities planned or selected to allow students to demonstrate the
core learning outcomes
• future learning opportunities for students who have not yet demonstrated the core learning
outcomes and to challenge and extend those students who have already demonstrated the
core learning outcomes
• the extent to which activities matched needs of particular groups of students and reflected
equity considerations
• the appropriateness of time allocations for particular activities
• the appropriateness of resources used.
Information from this evaluation process can be used to plan subsequent units of work so that
they build on, and support, student learning. The evaluated units of work may also be adapted
prior to their reuse. For further information, refer to the ‘Curriculum evaluation’ section of the
sourcebook guidelines.
© The State of Queensland (The Office of the Queensland Studies Authority) 2003
3
Technology
Designing a hydroponic system
Links
Links to other
key learning
areas
Activities from this module can be used as part of an integrated unit that makes links to other
key learning areas. When incorporating this module into an integrated unit of work, teachers can
select activities that provide opportunities for students to demonstrate learning outcomes from
other key learning areas and identify anticipated evidence of students' demonstrations of these
learning outcomes. It is important, however, that the integrity of the processes and concepts
within key learning areas is maintained.
Contributions
to the crosscurricular
priorities
This module could link to the following key learning areas:
• English
• Mathematics
• Science
This module contributes to students’ development of the cross-curricular priorities:
• literacy as students keep a journal of what is happening in the plot each week,publish
updates in a class newsletter,give oral presentations and compile written presentations
• numeracy as students collect information,use a spreadsheet to construct graphs, use
formulas in spreadsheets, investigate money concepts and calculate areas
• lifeskills as students development personal, social and self-management skills
• a futures perspective as students envision and work towards preferred futures by using the
knowledge,practices and dispositions of ‘working technologically’.
The valued
attributes of a
lifelong learner
The overall learning outcomes of the Queensland Years 1 to 10 curriculum contain elements
common to all key learning areas and collectively describe the valued attributes of a lifelong
learner.
The following points indicate how various activities in this module might contribute towards the
development of these attributes.
Knowledgeable person with deep understanding
• draws together knowledge from a range of areas (including mathematics, science, history
and the arts) to design and develop creative solutions
• explores issues behind challenges and predict the impacts of the products of technology on
people and environments
• develops understandings about investigation, ideation, production and evaluation.
Complex thinker
• uses inductive and deductive thinking to make predictions about the impacts of the
processes and products of technology
• predicts and identify possible sources of error and bias in research and test results
• judges the relevance, reliability and validity of data and information.
Active investigator
• examines and cause-and-effect relationships within systems, and refine systems by finding
and rectifying faults or design flaws
• generates and access information from a variety of sources.
Responsive creator
• uses imagination, originality, intuition, enterprise and aesthetic judgment
• envisions and generate a range of potential solutions.
Effective communicator
• uses a variety of methods to communicate design ideas effectively to a range of audiences
• uses accepted standards and forms for measurement, calculation, and written and visual
representations.
Participant in an interdependent world
• works individually and collaboratively on a variety of design challenges with confidence and
initiative
• negotiates with others and resolve conflict in appropriate ways as they work towards
common goals and share equipment and resources.
Reflective and self-directed learner
• critically evaluates processes and products of technology
• displays self-motivation and perseverance in seeing projects through to completion.
4
© The State of Queensland (The Office of the Queensland Studies Authority) 2003
Technology
Designing a hydroponic system
Assessment strategies
The assessment opportunities outlined are examples of how to assess students’ demonstrations
of the identified learning outcomes. As often as possible, negotiate assessment with students and
support a variety of ways of demonstrating the learning outcomes. Reflect with students on
evidence gathered when making judgments about their demonstrations of learning outcomes.
Some students may require more time and/or other contexts in which to demonstrate these
learning outcomes. Other modules may provide such time and/or contexts.
Suggestions for gathering information about student learning are provided in the activities section
of this module. The table below provides descriptions of anticipated evidence that teachers might
gather to support their judgments about students' demonstrations of learning outcomes and
suggests sources of evidence. The table is neither exhaustive nor mandatory. Once sufficient
evidence has been collected, judgments can be made about students' demonstrations of learning
outcomes.
[This table spreads over two pages.]
Core learning outcomes
Anticipated evidence
Sources of evidence
TP 3.1 Students examine
knowledge, ideas and data from a
range of sources and establish the
relevance of this information when
meeting design challenges.
Research various sources, such
as the library and Internet.
Anecdotal records observation of
students as they participate in
planned activities.
TP 3.2 Students collaboratively
generate design ideas and
communicate these using
presentations, models and
technical terms.
Work in groups to develop design
proposals.
Students’ detailed design
proposals.
Collaborate with experts to
generate ideas.
Feedback sheets.
TP 3.3 Students cooperatively
develop and follow production
procedures to make products that
reflect their design ideas.
Work together to describe and
sequence steps.
Consultation with students to
verify the evidence gathered.
Follow identified production
procedures.
Observation of students as they
participate in planned activities.
Modify procedures to suit
changing circumstances.
Students’ products.
Establish the relevance, reliability,
currency and credibility of the
information.
Present 2D presentations/ 3D
models and use technical terms
to describe major features.
Consultation with students to
verify the evidence gathered.
Observation of students as they
participate in planned activities.
Monitor the quality of their work.
Adhere to safety procedures.
TP 3.4 Students test and judge
how effectively their own and
others’ processes and products
meet the design challenge.
Carry out tests on products and
processes.
Peer and self-assessment sheets.
Make judgments about
appropriateness.
Students’ presentations.
Technology project folios.
Rate effectiveness and efficiency.
Make comparisons between
different products.
Identify requirements or
constraints.
© The State of Queensland (The Office of the Queensland Studies Authority) 2003
5
Technology
INF 3.1 Students describe
advantages and disadvantages of
different sources and forms of
information.
Designing a hydroponic system
Identify different sources of
information that are appropriate
to their needs.
Observation of students as they
participate in planned activities.
Technology project folios.
Compare information to
determine appropriateness.
Consider how different forms of
information achieve different
effects.
INF 3.2 Students select and use
techniques for generating,
modifying and presenting
information for different purposes.
Organise information and record
data using tables they have
designed.
MAT 3.1 Students choose
materials according to various
characteristics that best suit the
product and user.
Identify a number of
characteristics that make a
material suitable.
Observation of students as they
participate in planned activities.
Identify purposes of products and
describe how some materials
support these purposes.
Students’ work samples.
MAT 3.2 Students select and use
suitable equipment and techniques
to combine materials accurately in
order to meet design requirements.
Combine materials accurately in
order to meet design challenges.
Observation of students as they
participate in planned activities.
Select and use appropriate
equipment for the task.
Students’ work samples.
SYS 3.1 Students identify and
describe relationships between
inputs, processes and outputs in
systems.
Identify inputs, processes and
outputs in systems.
Technology project folios.
Technology project folios.
Students’ work samples.
Use equipment such as
scanners, digital cameras and
computers to present information.
Technology project folios.
Students’ products.
Students’ work samples.
Use simple flow charts, diagrams
and drawings to record
information.
Describe the effects that may
arise if an input or process is
changed.
SYS 3.2 Students assemble and
trial systems they design by
considering inputs, processes and
outputs.
Design and assemble systems.
Students’ work samples.
Develop a system to achieve a
specific output.
Peer and self-assessment.
Describe the function of
components in a simple system.
Trial systems they have
designed.
6
© The State of Queensland (The Office of the Queensland Studies Authority) 2003
Technology
Designing a hydroponic system
In gathering evidence to make judgments about students’ demonstrations of core learning
outcomes, it may be necessary to look at the level before and after Level 3 The following table
indicates evidence of the level after. Students may be demonstrating core learning outcomes at
another level.
[This table spreads over two pages.]
Core learning outcomes
Anticipated evidence
Sources of evidence
TP 4.1 Students use consultative
methods to gather knowledge,
ideas and data when researching
alternatives within design
challenges.
Use a variety of sources and
range of methods to gather
information.
Observations of students as they
participate in planned activities.
Observe the products developed
by others in order to incorporate
features in their own designs.
Consultation with students to
verify the evidence gathered.
TP 4.2 Students generate design
ideas through consultation and
communicate these in detailed
design proposals.
generate possible solutions and
alternatives and communicate
these to others.
Detailed design proposals.
Plan and organise a consultation
process.
Anecdotal records.
Feedback sheets.
Observations of students as they
participate in planned activities.
Annotate design ideas to show
changes made following
consultation.
Collaborate with others to
develop a range of design
alternatives.
Use lists and flow charts to
identify what is needed to
implement a proposal.
Recognise the importance of
scale in plans and draw plans
from several views.
TP 4.3 Students identify and make
use of the practical expertise of
others when following production
procedures to make products for
specific users.
Share and refine design ideas
before commencing and at
regular intervals throughout the
production process by
collaborating with peers or others
with specialist knowledge.
Consultation with students to
verify evidence.
Observations of students’
participation in activities.
Products.
Document the decisions made
while developing and modifying
their products in their Technology
project folios.
Critically reflect on production
processes to evaluate
effectiveness and efficiency.
Keep a working diary.
TP 4.4 Students gather feedback
to gauge how well their design
ideas and processes meet design
challenges and how effectively
products meet the needs of
specific users.
Use feedback to design criteria
that could be used to select one
design proposal from a range of
alternatives.
Reflect on their final design by
comparing their finished product
with their original idea.
Feedback sheets.
Peer- and self-assessment
sheets.
Technology project folios.
Students’ presentations.
Demonstrate how their ideas
evolved by presenting their
product to others, pointing out
special features and explaining
why these features are included.
© The State of Queensland (The Office of the Queensland Studies Authority) 2003
7
Technology
Designing a hydroponic system
Core learning outcomes
Anticipated evidence
Sources of evidence
INF 4.1 Students analyse sources
and forms of information and
match these to the requirements of
design challenges.
Recount ways in which they have
accessed and used information
purposefully.
Observations of students as they
participate in planned activities.
INF 4.2 Students apply techniques
for transforming and transmitting
information for different audiences.
Record class ideas on how to
translate one source of
information into another.
Technology project folios.
Communicate ideas using clearly
labelled diagrams and charts.
Technology project folios.
Work samples.
Convert data to graphical/
pictorial presentations.
Consider which information is
needed for special audiences
when generating presentations or
charts.
MAT 4.1 Students explain how
characteristics of materials affect
ways they can be manipulated.
Conduct basic testing and
comparison of materials.
Observations of students as they
participate in planned activities.
Compare the performance,
function and cost of similar and
different materials.
Technology project folios.
Work samples.
Match characteristics and
properties of materials to
requirements.
MAT 4.2 Students employ their
own and others’ practical
knowledge about equipment and
techniques for manipulating and
processing materials in order to
enhance their products.
Select tools and materials to
achieve their design purposes.
Observation of students as they
participate in planned activities.
Identify and discuss the effects
that various materials have on:
• cost
• techniques used to manipulate
the material
• equipment used.
Work samples.
SYS 4.1 Students identify and
explain the logic of systems and
subsystems.
Identify and explain parts within a
whole system.
Technology project folios.
Students’ products.
Work samples.
Identify how systems and
subsystems work together.
Alter subsystems to change the
operation of a more complex
system.
Draw charts explaining the
operation of systems and
subsystems.
SYS 4.2 Students incorporate
feedback to refine and modify
systems and/or subsystems.
8
creating flow charts and diagrams
to devise and explain systems.
Work samples.
Monitor and test system:
• reliability
• durability
• efficiency
• stability.
Peer- and self-assessment.
Students’ products.
© The State of Queensland (The Office of the Queensland Studies Authority) 2003
Technology
Designing a hydroponic system
Background information
Terminology
In this module students have opportunities to become familiar with and use the following
terminology:
hydroponics
monitor
reservoir
inputs
outputs
solenoid
irrigation
processes
timer
School authority policies
Teachers need to be aware of and observe school authority policies that may be relevant to this
module.
Safety policies will be of particular relevance to some of the activities that follow. It is essential
that teacher demonstrations and student activities are conducted according to procedures
developed through appropriate risk assessments at the school.
In this module, teachers may need to consider safety issues relating to:
• chemical fertilisers
• equipment and materials
• sun safety.
Equity considerations
This module provides opportunities for students to increase their understanding and appreciation
of equity and diversity within a supportive environment. It includes activities that encourage
students to:
• be involved
• work individually or in groups
• value diversity of ability, opinion and experience
• value diversity of language and cultural beliefs
• support one another in their efforts
• become empowered to communicate freely
• negotiate
• accept change.
Some students with disabilities may need assistance with some activities. Advice should be
sought from their support teachers. It is important that these equity considerations inform decision
making about teaching strategies, classroom organisation and assessment.
© The State of Queensland (The Office of the Queensland Studies Authority) 2003
9
Technology
Designing a hydroponic system
Activities
Introductory activities: Traditional growing of plants
Focus
TP 3.1 Students examine knowledge, ideas and data from a range of sources and establish the
relevance of this information when meeting design challenges.
INF 3.1 Students describe advantages and disadvantages of different sources and forms of
information.
INF 3.2 Students select and use techniques for generating, modifying and presenting information
for different purposes.
Activities
Start the activity by discussing where the food we eat comes from. Narrow the discussion to
strawberries and tomatoes. ‘How could we grow our own?’
Brainstorm ‘What we know’ and ‘What we need to know’.
List ways to verify ‘what we know’ and find answers to ‘what we need to know’ — for example,
by accessing encyclopaedias and the Internet and contacting local experts.
Use research activities to find information on growing strawberries and tomatoes. Collect written
facts and clippings and present them on a display board.
Conduct a formal lesson on plants. Look at how plants grow and discuss root systems and
leaves.
Refine ‘what we need to know’. This may have increased after the initial research if students
discovered areas where they didn’t have much knowledge or the information they found
presented them with more questions. Arrange the information into questions.
Find a local farmer preferrably one who grows tomatoes or strawberries and visit their farm.If
feasible or invite the farmer to your classroom. Encourage students to present their questions to
the expert and gain as much information they can. Stress that talking to experts is a good way of
obtaining knowledge gained by someone else.
From the information gathered, draw up a large table with two columns headed ‘What
strawberries need’ and ‘What tomatoes need’. Brainstorm a list of the materials you will need to
grow these plants.
Assessment
10
Sources of evidence could include:
• observation of students’ participation in planned activities
• anecdotal records
• consultation with students to verify the evidence gathered.
© The State of Queensland (The Office of the Queensland Studies Authority) 2003
Technology
Designing a hydroponic system
Introductory activities: Hydroponics
Focus
TP 3.1 Students examine knowledge, ideas and data from a range of sources and establish the
relevance of this information when meeting design challenges.
INF 3.1 Students describe advantages and disadvantages of different sources and forms of
information.
INF 3.2 Students select and use techniques for generating, modifying and presenting information
for different purposes.
Activities
Introduce the activity by conducting a brainstorming session to find out what the students know
about hydroponics. Ask how we could learn more.
Search for information on hydronponics using the library and internet.Record this information in
Technology project folios.
Divide the students into small groups and give each group an article on hydroponics. Ask the
students to select facts from their article and write them on a slip of paper and place them in a
pile. Sort out all the facts and group them under subheadings. Display all the information around
the classroom for reference during the design challenge.
Visit a hydroponics farm if feasible to obtain information.Alternatively, invite someone with
knowlegde and expertise in hydroponics to visit the class and work with the students. Look for
similarities and differences between the traditional and hydroponic methods of growing
strawberries and tomatoes.
Take note of the different methods of growing strawberries hydroponically.Discuss the positive
and negative impacts and consequences of both systems. Use the Internet to email hydroponic
farmers to gather more information.
Ask students to use the knowledge they have gained to design a hydroponic system for
tomatoes and strawberries.
Assessment
Sources of evidence could include:
• anecdotal records
• consultation with students to verify the evidence gathered
• observation of students’ participation in planned activities
• Technology project folios.
© The State of Queensland (The Office of the Queensland Studies Authority) 2003
11
Technology
Designing a hydroponic system
Developmental activities: Traditional growing of plants
Design challenge 1
Design and create a hydroponic system for growing strawberries and tomatoes.
Design challenge 2
Design and create an irrigation system for watering ground strawberries and tomatoes.
Focus
TP 3.2 Students collaboratively generate design ideas and communicate these using
presentations, models and technical terms.
TP 3.3 Students cooperatively develop and follow production procedures to make products that
reflect their design ideas.
TP 3.4 Students test and judge how effectively their own and others’ processes and products
meet the design challenge.
Select a patch of ground for growing the strawberries and tomatoes. Obtain seedlings
(strawberries and tomatoes).
Assist students to work out how much ground they will need. They should know from their
research that strawberries need to be more than 30 cm apart.
Pose a range of questions — for example, How many rows will you need? Should the rows be
raised and why? How deep should you plant the seedlings? Students should compile a written
report that includes as much of the information they have gathered as possible.
Repeat this investigation process for the irrigation system.Collect and record as much
information as possible. The design of the irrigation system needs to be incorporated into the
design of the garden bed.The irrigation system will need to be established before planting the
seedlings.
Collect and discuss the written reports. Ask each student to use all the information they have to
design a landscaping plan. Include a top-view to-scale plan of the patch that shows the layout of
the plants and the irrigation system.
As a class, design a system for growing tomatoes and strawberries. Invite an expert from a local
farm and an irrigation company (if available) to look at the system and offer advice. Stress to the
students that advice from experts will help them in any project.
Once the design process is complete, construct the irrigation system and prepare and plant the
strawberries and tomatoes.
Discuss any information the students discovered about disease and pests. Discuss and design a
plan to combat these problems. Consider whether or not to use pesticides. Discuss the positive
and negative impacts and consequences and invite the class to decide what would be best to
use. Present the findings to the local farmer and ask for advice.
Establish and implement a plan to solve the problem of diseases and pests.
Design a system for monitoring the patch that includes watering and weeding and picking the
strawberries and tomatoes.
Discuss what to do with the strawberries and tomatoes — for example, eat them or sell them.
Assessment
12
Sources of evidence could include:
• detailed design proposals
• feedback sheets
• observation of students’ participation in planned activities
• consultation with students to verify the evidence gathered
• students’ products.
© The State of Queensland (The Office of the Queensland Studies Authority) 2003
Technology
Designing a hydroponic system
Developmental activities: Hydroponics
Focus
SYS 3.1 Students identify and describe relationships between inputs, processes and outputs in
systems.
SYS 3.2 Students assemble and trial systems they design by considering inputs, processes and
outputs.
MAT 3.1 Students choose materials according to various characteristics that best suit the
product and user.
MAT 3.2 Students select and use suitable equipment and techniques to combine materials
accurately in order to meet design requirements.
Activities
Ask students to present their the hydoponic system design ideas, as an oral report and justify
each decision they have made. Discuss the ideas and look for good points or potential
problems.
As a class, design a hydroponic system for growing strawberries and tomatoes. Invite local
hydroponic farmers (if available) to examine the designs and make comments or suggestions.
Students need to draw up a cross-section view of the design. Label all the parts and describe
how the system will work.
Small groups of students should be involved in the construction of the strawberry and tomato
systems. Involve the students in as much of the construction as possible.
Design a watering system. Over the first week, work out how long to set the digital timer for and
how often.(if one is included in the plan) The plants should not be too dry, but too much water is
a waste of valuable (and expensive) nutrients. Check that the potting medium is constantly
moist and that the leaves are not yellow or curling, which indicates a lack of water or nutrients.
As the plants get bigger, they will require more water and nutrients. If you are not sure how
much they need, consult an expert.
Discuss any information the students discovered about disease and pests. Discuss and design
a plan to combat these problems. Consider whether or not to use pesticides. Discuss the
positive and negative impacts and consequences and invite the class to decide what would be
best to use. Present the findings to the local farmer and ask for advice. If a local expert is not
available, consider contacting an expert using the Internet.
Establish and implement a plan to solve the problem of diseases and pests.
Design a system for monitoring the patch that includes watering and weeding and picking the
strawberries and tomatoes.
Assessment
Sources of evidence could include:
• observation of students’ participation in planned activities
• Technology project folios
• students’ work samples and products
• peer and self-assessment.
© The State of Queensland (The Office of the Queensland Studies Authority) 2003
13
Technology
Designing a hydroponic system
Culminating activities
Focus
In this phase students test and judge how effectively their own and others’ processes and
products meet the design challenge.
Activities
Brainstorm ways in which the success of the project can be measured.
Collect information about the strawberries and tomatoes. Once a week, count the flowers and
green strawberries and record the data (Student resource 1). Graph this information using a
comparative line graph and a spreadsheet. Grade the tomatoes and strawberries by mass and
record how many are picked and how many are lost to pests or disease.
Assess the quality of the strawberries and tomatoes. Students can be encouraged to assess
taste, appearance, size and weight. For example, mass all the strawberries and tomatoes that
are picked and work out the mean, medium and mode.
Record any disease and pest problems. Outline the action that was taken and the results of the
action.
Design and construct a survey to give to the people who eat the strawberries and tomatoes.
Arrange the questions so that they allow a comparison of the traditional and hydroponic
systems.
Once all the strawberries and tomatoes have been harvested, discuss ways in which the
success of the various projects can be assessed. Consider comparing numbers and weight of
fruit harvested, taste of fruit, length of harvest time, loss of fruit and to what pests and disease.
Look at sales of fruit and when the fruit was most popular. Encourage students to design a
survey for customers to determine what worked well and what could be improved — for
example, packaging and presentation. Ask students to make inferences and recommendations
for future projects.
Assessment
14
Sources of evidence could include:
• peer and self-assessment sheets
• student presentations
• Technology project folios.
© The State of Queensland (The Office of the Queensland Studies Authority) 2003
Technology
Designing a hydroponic system
Data collection sheet
Student resource 1
F — flowers G — green fruit P — picked fruit
Hydroponic
Strawberries
Week
F
G
Ground
Tomatoes
P
F
G
Strawberries
P
F
G
Tomatoes
P
F
G
P
1
2
3
4
5
6
7
8
© The State of Queensland (The Office of the Queensland Studies Authority) 2003
15
Technology
Designing a hydroponic system
Acknowledgments and support materials
Acknowledgments
Grateful acknowledgment is made to the following organisations and/or people for granting
permission to use copyright material and for assistance in preparation of this module:
Teachers, students and staff of the Kallangur State School
Andrew Swales, teacher
Linda McGill, teacher
Laurie Henneberg, groundsman
John Bench, traditional strawberry farmer
Brian Biddell, hydroponics strawberry farmer
David Bray, hydroponics tomato farmer
SA Hydroponics, Lawnton
References
Goss, J The Simplified Hydroponics Workbook (A Simplified Guide to Soilless Gardening), Rocky
Top Publishing, Canada.
Jones L 1990 Home Hydroponics and How to Do It!, Crown Publishing, United Kingdom.
James Sholto Douglas 1986 Beginner's Guide to Hydroponics: Soilless Gardening, Pelham
Publishing, United Kingdom.
Resh, H. 1990, Hydroponic Home Food Gardens, Woodbridge Press Santa Barbara, California.
Resh, H. 1989, Hydroponic Food Production, 4th edn, Woodbridge Press Santa Barbara,
California.
Resh, H. 1993, Hydroponic Tomatoes for the Home Gardener, Woodbridge Press Santa Barbara,
California.
Taylor, J.D. 1983, Grow More Nutritious Vegetables Without Soil, Parkside Press Publishing,
Santa Anna, California.
Websites
(All websites listed were accessed in September 2002.)
Ask an Expert, www.cln.org/int_expert.html/ Links to ‘expert’ websites.
Homegrown Hydroponics Inc, www.hydroponics.com/ General hydroponics information and
resources.
Home Hydroponics, www.ext.vt.edu/pubs/envirohort/426-084/426-084.html/ Detailed information
on hydroponics.
Pipe Dreams Hydroponics www.hydroponicsonline.com/ General information and hydroponics
links.
Contacts
Dave Nebauer, Hydroponics Industry Support Officer, Central Coast Regional Development
Corp., Phone: (02) 4323 9587
Hydroponics Association of Australia, Phone: (07) 5496 7529
Hydroponics Industry Support Officer, Central Coast Regional Development Corporation,
Phone: (02) 4323 9587
John Kennedy, Hydroponics Association of Australia, Phone: (07) 5496 7529
Paul and Darren Borg, Borg’s Hydroponics - Lettuce Growers, Warnervale,
Phone: (02) 4392 7726
Rick Slennett, Simply Hydroponics - Gold Coast, Phone: (07) 5537 4433
Simply Hydroponics — Gold Coast, Phone: (07) 5537 4433
Steven Carruthers, Publisher — “Practical Hydroponics”, Phone: (02) 9905 9933
This sourcebook module should be read in conjunction with the following Queensland
Studies Authority materials:
Years 1 to 10 Technology Syllabus
Years 1 to 10 Technology Sourcebook Guidelines
Technology Initial In-service Materials
Technology CD-ROM
16
© The State of Queensland (The Office of the Queensland Studies Authority) 2003
Technology
Designing a hydroponic system
Copyright notice
© The State of Queensland (The Office of the Queensland Studies Authority) 2002
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© The State of Queensland (The Office of the Queensland Studies Authority) 2003
17
The History of Hydroponics
As seen in Growing Edge Magazine
Hydroponics basically means working water ("hydro" means "water" and "ponos" means
"labor"). Many different civilizations have utilized hydroponic growing techniques throughout
history. As noted in Hydroponic Food Production (Fifth Edition, Woodbridge Press, 1997, page
23) by Howard M. Resh: "The hanging gardens of Babylon, the floating gardens of the Aztecs
of Mexico and those of the Chinese are examples of 'Hydroponic' culture. Egyptian hieroglyphic
records dating back several hundred years B.C. describe the growing of plants in water."
Hydroponics is hardly a new method of growing plants. However, giant strides have been
made over the years in this innovative area of agriculture.
Throughout the last century, scientists and horticulturists experimented with different methods
of hydroponics. One of the potential applications of hydroponics that drove research was for
growing fresh produce in nonarable areas of the world. It is a simple fact that some people
cannot grow in the soil in their area (if there is even any soil at all). This application of
hydroponics was tested during World War II. Troops stationed on nonarable islands in the
Pacific were supplied with fresh produce grown in locally established hydroponic systems.
Later in the century, hydroponics was integrated into the space program. As NASA considered
the practicalities of locating a society on another plant or the Earth's moon, hydroponics easily
fit into their sustainability plans. This research is ongoing.
But by the 1970s, it wasn't just scientists and analysts who were involved in hydroponics.
Traditional farmers and eager hobbyists began to be attracted to the virtues of hydroponic
growing. A few of the positive aspects of hydroponics include:
•
The ability to produce higher yields than traditional, soil-based agriculture
•
Allowing food to be grown and consumed in areas of the world that cannot support
crops in the soil
•
Eliminating the need for massive pesticide use (considering most pests live in the
soil), effectively making our air, water, soil, and food cleaner
Commercial growers are flocking to hydroponics like never before. The ideals surrounding
these growing techniques touch on subjects that most people care about, such as helping end
world hunger and making the world cleaner. In addition to the extensive research that is going
on, everyday people from all over the world have been building (or purchasing) their own
systems to grow great-tasting, fresh food for their family and friends. Educators are realizing
the amazing applications that hydroponics can have in the classroom. And ambitious
individuals are striving to make their dreams come true by making their living in their
backyard greenhouse, selling their produce to local markets and restaurants.
And now that so many people from so many different walks of life are involved in hydroponics
and its associated disciplines (such as aeroponics and aquaponics), progress is coming faster
than ever before.
Title: Where is the Dirt? A Lesson in Hydroponics
Overview/Annotation:
This lesson will be developed around hydroponic gardening, the growing of plants without soil. Using
the Internet, students will research hydroponics and share their knowledge with the class. A classroom
hydroponic garden will be constructed for observation.
Content Standard(s):
SC(4)
5. Describe the interdependence of plants and animals.
TC2(3-5)
8. Collect information from a variety of digital sources.
Local/National Standards: Primary Learning Objective(s): Students will explain how plants can
grow without soil.
Additional Learning Objective(s): Students will apply knowledge of hydroponic gardening to create
a classroom garden.
Approximate Duration of the Lesson: Greater than 120 Minutes
Materials and Equipment:
Aquarium, aerator, polystyrene (foam board)- one inch thick, fertilize (such as Rapid-Grow or MiracleGrow), Jiffy pellets, seeds (small vegetable seeds, such as lettuce, spinach, basil, tomatoes etc.), plastic
tray(approximately the same area as the aquarium)
Technology Resources Needed:
Computers with Internet access, digital camera
Background/Preparation:
The teacher should become familiar with the instructions for building a hydroponic garden. Read all
instructions for nutrients and fertilizers carefully.
Procedures/Activities:
1.)Pose the following question to students: "Can plants grow without soil?" Tally student responses and
display results. Tell students that they will be conducting research on the computer to answer this
question.
2.)Ask students how they could use the computer to answer the question, "Can plants grow without
soil?" Direct them towards the understanding that the Internet can be used to answer questions and find
information.
3.)Brainstorm key words that may be used to find the answer to the question, "Can plants grow without
soil?" List some words and phrases on the board for students to refer to when conducting their
searches. Group students in pairs at computer stations. (It may be helpful to bookmark approved search
engines for student use prior to beginning this lesson.) Give students approximately 10 minutes to
search the Internet and record their findings.
4.)Have students return to the group to share what they have found regarding growing plants without
soil. At a basic level all students should have discovered that plants can grow without soil. Ask students
if they learned anything else about this topic and allow students to discuss findings.
5.)If students have not already discovered the scientific term hydroponics, introduce it. Direct students
to the website below. Pass out the handout "Understanding Hydroponics" (see attached) for students to
complete once they have read the information on the website. (Alternatively, teacher may want to
create a slideshow presentation to introduce students to hydroponics.)
(Introduction to Hydroponics)
6.)Ask students what the advantages might be to using hydroponics. Record student ideas then have
them return to computer stations to research the advantages of hydroponics. (Again, if necessary
brainstorm key words to use in the Internet search.) Students will share what they have learned and
compare their findings with their original ideas.
7.)Tell students that the class will be starting a hydroponic garden. Students will record information
concerning the garden in a class journal. See attached instructions to construct the hydroponic garden.
8.)In the class journal students should record the amount of water placed in the aquarium at the
beginning and throughout the growth cycle. Plant growth should be observed weekly. Record plant
size, color and any other changes. Students can use a digital camera to take pictures of the garden on a
weekly basis and include the pictures in the class journal.
Attachments:**Some files will display in a new window. Others will prompt you to download.
Instructions for classroom hydroponic garden.doc
UNDERSTANDING HYDROPONICS.doc
Assessment Strategies:
Teacher observation of classroom participation, "Understanding Hydroponics" Internet search
document, and checklist to ensure that all students participate in class journal of plant observations will
be used for assessment.
Extension:
1) Create several different kinds of hydroponic gardens to determine which are most effective. 2)
Experiment with different nutrient solutions to determine which are best for plants.