Caring for Fresh Cut Flowers
and Foliage
H
AVE YOU or someone you know received cut
flowers that died in a matter of days? It is
disappointing to see flowers quickly die. Have you
asked why they declined rapidly or what you could have
done to make them live longer? This unit will address
the care of cut flowers.
Objective:
þ
Examine the care of fresh cut flowers and foliage.
Key Terms:
Ñ
acidic
alkaline
bent necks
conditioning
ethylene inhibitors
floral preservatives
graded
hard water
hardened
precooled
salinity
senescence
soft water
stem blockage
transpiration
turgid
vase life
Proper Care
Fresh cut flowers and foliage are living things though they have been removed from plants.
However, once they have been removed, they begin to decline and die. Two needs for extending the life of cut flowers and foliage are water and sugar.
A flower is 90 percent water. Plant cells filled with water are said to be turgid. Even after
fresh flowers have been removed from plants, they continue with life processes, such as
photosynthetic and cellular respiration. These processes require the use of water.
The quality of water is extremely important for cut flowers. The pH of water is a critical
factor that determines water quality. A pH test of the water can be conducted to determine
whether water is acidic or alkaline. An acidic pH has a reading below 7. pH readings above 7
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indicate an alkaline solution.
Slightly acidic water improves water
uptake by fresh cut flowers and
foliage. Floral preservatives added to
water increase the acidity, thereby
increasing water uptake.
Water is classified as either hard
water, which contains a high level
of minerals, or soft water, which
has been treated to lower the mineral
level. Hard water has a high pH and
H
H
H
H H
H
H
H
H
H
H
H H
is highly buffered, meaning it is
H
H
H
H
H
H
H
H
H
H
resistant to a change in pH. Softened
pH
=
7
pH
=
12
pH = 4
water has been treated with salts to
Neutral
Alkaline
Acidic
remove dissolved minerals. The
Higher pH = more hydrogen ions
addition of salts to the water lowers
the water quality for flowers. Salin- FIGURE 1. Adding floral preservatives will correct alkaline and neutral pH.
ity is the measurement of total dissolved salts in water. Salts clog the xylem of the floral stem, preventing water movement and
resulting in wilting and weakening of the stem. Salinity needs to be less than 200 ppm.
Sugars are the food source for cut flowers. The two most common sugars are sucrose and
dextrose. A flower gets these sugars from stores in the flower tissues, through photosynthesis,
or through supplemental sugars provided in a floral
preservative.
CONDITIONING
Conditioning is the preparation of cut flowers
and greens when they arrive at the design site. The
conditioning process involves the cutting of stems,
adequate solution uptake by the plant materials, and
cooling.
Cutting Stems
Flower stems should be re-cut. Leaves should be
removed from the stems so that no leaves will be
submerged in the water solution.
Solution Preparation
Flowers should be placed in water that is approximately 100° to 110°F (38° to 43°C), or about the
FIGURE 2. Condition flowers in warm preservative
solution.
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temperature of a warm bath. Warm water speeds uptake and contains less air than cold water.
Allow the flowers to take up water at room temperature for several hours before placing them
in a cooler.
Cooling
Once the flowers are full of water, they can be placed in a cooler that is 34° to 38°F (1° to
3°C). Floral coolers are better than refrigerators because they provide controlled humidity levels in addition to cooling. Flowers that have been conditioned are said to be hardened and
ready for use in arranging.
Conditioning Steps
Conditioning plant materials includes the following steps:
1. Unpacked and inspect flowers upon receipt. A report should be made to the wholesaler
of any problems or mistakes.
2. Prioritize the order of processing. Condition the wilt-prone and expensive flowers first.
3. Remove sleeves, ties, and any foliage that might contact water in a container.
4. Under warm water, re-cut all stems, removing 1/2 to 1 inch. Professional underwater
cutting devices are recommended.
5. Use specific treatment solutions as needed.
6. Place flowers in floral preservative solution mixed at the proper concentration. Too
high a concentration encourages bacterial growth; too low a concentration can cause
toxicity.
7. Let the flowers remain at room temperature for two to three hours to increase water
uptake.
8. Place the flowers in a
cooler set at 34° to 38°F
(1° to 3°C), with a high
humidity level and constant light.
Flowers with milky stems,
such as poinsettias and poppies,
should be treated by dipping them
in boiling water for five seconds
and then placing them in a floral
preservative solution. An alternative method is exposing the cut
FIGURE 3. A bent-neck rose is a common site.
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end to a match flame without burning the stem or placing it in very warm floral preservative
solution.
Roses that have lost turgidity near the flower heads are called bent necks. They can be
revived by re-cutting the stems under water and placing the entire stems in a warm preservative solution.
FACTORS THAT AFFECT VASE LIFE
Many factors contribute to the vase life of fresh cut flowers and foliage. Vase life is the
length of time cut flowers and foliage live after they have been cut. Sanitation, senescence,
wilting, harvesting, ethylene, and disease or damage are some of the factors.
Sanitation
An important factor in the handling of cut flowers and greens is sanitation. Sanitation, or
cleanliness, improves the vase life of flowers. Hands, tools, knives, shears, containers, and work
areas need to be kept sanitary. Introduction of bacteria and organisms can be avoided by cleaning work areas, coolers, and containers regularly.
Senescence
As soon as a flower is cut from the mother plant, it begins to deteriorate. This is partly
because the flower no longer has a water or food source. The flower will eventually die. The
decline is referred to as senescence. Senescence is influenced by genetics, lack of water,
time of harvest, ethylene, and disease or damage.
The life of each flower is based on its genetics. The natural lives of flowers differ between
species. The flowers of the daylily live just 1 day. Dutch irises live 3 to 5 days, and roses 5 to 7
UNDER INVESTIGATION…
LAB CONNECTION: Floral Preservatives
Floral preservatives are used to extend the life of cut flowers. Floral preservatives used in the
trade have three main ingredients: a sugar, an acidifier, and a bactericide.
Over the years many materials have been considered by some people to be effective floral
preservatives. Some of these are aspirin, pennies, and Coca-Cola®. Perhaps you have heard of
others.
You can design your own experiment to determine the effectiveness of these treatments in
comparison to a commercial preservative. Prepare bud vases with different treatments you
would like to test, including one commercial preservative. Label the vases with the names of the
treatments, and place fresh cut flowers from the same bunch in each vase. Set the vases aside.
Observe the flowers daily. Which treatments were the most effective? Which were the least
effective?
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days. Carnations last 10 to 14 days, and chrysanthemums 14 to 21 days. The goal is to obtain
the maximum life of each flower as allowed by nature.
Wilting
Wilting is caused by the inability of plant tissues to absorb enough water to replace water
lost by transpiration. The rate of transpiration increases in warm environments with low
humidity. Transpiration can be reduced by keeping
plant materials from drafts and avoiding
overhandling flowers.
Blocked vascular tissue can restrict the movement of water within a plant and cause wilting.
Stem blockage is the most common cause of
poor absorption. The xylem becomes clogged, and
movement of water through the stem is restricted.
Harvesting
The timing of flower harvest influences flower
life. The time of day when flowers are cut is important. Flowers should never be cut when they are
wilted. Therefore, avoid cutting in the heat of the
day. Evening is the best time, because plants have
been making sugars throughout the day. Morning is
the second best time, because plants are full of
water.
The stage of flowering should be considered. The
best time to harvest is just before a flower is fully
open. Exceptions to the rule include the daisy and
flowering bulb crops, which are
harvested in bud stage, and the
calla lily, which will not develop
further once it is cut.
FIGURE 4. Most flowers are harvested just before
the flowers are fully open.
Ethylene
Ethylene gas promotes senescence. Ethylene gas is a natural
plant hormone produced by aging
flowers, foliage, fruits, and vegetables. Common signs of ethylene
exposure include large numbers
of fallen petals, dropped florets,
and yellowing leaves. Fresh cut
FIGURE 5. Ethylene damage on chrysanthemums.
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flowers should be placed in an environment free of ethylene gas. Growers and wholesalers prevent this damage by using ethylene inhibitors, which are products that block or tie up the
gas. Growers and wholesalers also strive to keep storage areas free of aging, decaying plant
materials. Fruit should not be stored in a floral cooler because it produces ethylene gas.
Disease or Damage
Disease or damage shortens the life of floral materials. Flowers that arrive from the market
and those picked in the garden should be of the highest quality. They must be inspected for
disease and insect damage.
FLORAL PRESERVATIVES
Floral preservatives extend the life of cut flowers. A preservative contains a sugar as a
supplemental food source, an acidifier to decrease the chance of stem clogging, and a
bactericide to kill bacteria in a vase or stem. Pre-treatments are used before preservatives to
reduce ethylene exposure and to hydrate flowers that are wilt prone, such as gerberas and
roses. All flowers can benefit from a hydrating solution treatment.
PACKING AND SHIPPING
The majority of cut flowers sold in the United States are produced in foreign countries.
The commercial packing and shipping process affects the life spans of cut flowers in the floral
market.
First, flowers are graded, or separated into groups based on factors such as quality, uniformity, and size. They are also graded by stem quality, length, and strength. The flowers are then
placed in bundles and sleeved for shipping. Delicate flowers, such as Fuji mums and gerberas,
are individually sleeved.
After bundling, the flowers are boxed for shipment and precooled, which is a method of
quickly replacing the warm air inside the box with cool air. This process is also called dry packing. More delicate flowers, such as snapdragons and gladioli, are packed in hampers and stored
in an upright position. Most flowers are shipped via air and then via truck to the marketplace.
Summary:
2
Two needs for maintaining the health of cut flowers and foliage are water and
sugar. Slightly acidic water improves water uptake. Sugars come from stores in the
flower tissues, through photosynthesis, or through supplemental sugars provided in
a floral preservative.
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Conditioning is the preparation of cut flowers and greens before arranging. The
conditioning process involves the cutting of stems, adequate solution uptake by the
plant materials, and cooling.
Vase life is the length of time cut flowers and foliage live after they have been cut. It
is influenced by sanitation, senescence, wilting, harvesting, ethylene, and disease or
damage.
Floral preservatives extend the life of cut flowers. A preservative contains a sugar, an
acidifier, and a bactericide.
The commercial packing and shipping process affects the life spans of cut flowers in
the floral market. Flowers are graded, bundled, and sleeved for shipping. The flowers are boxed for shipment and precooled.
Checking Your Knowledge:
´
1. What do cut flowers need to stay healthy?
2. What is conditioning?
3. What influences vase life?
4. How do floral preservatives maintain vase life?
5. How are flowers packaged and shipped?
Expanding Your Knowledge:
L
Condition flowers received in the classroom before they are used for arranging.
Practice the conditioning procedure presented in this unit.
Web Links:
:
Cut Flowers and Florist Greens
http://www.ams.usda.gov/tmd/Tropical/cutflowers.htm
Conditioning
http://www.thegardener.btinternet.co.uk/conditioning.html
Conditioning and Storing Cut Flowers and Greens (PowerPoint
presentation)
http://72.14.203.104/search?q=cache:_CHgG2wmxZAJ:lr010.k12.sd.us
/care%2520and%2520handling.ppt+conditioning+flowers&hl=en&gl
=us&ct=clnk&cd=8
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