Growing the Future by Teaching Children in the Gardens
[email protected]
20 Miamiview Lane, Loveland, OH 45140
www.GrannysGardenSchool.org
513-324-2873
Putting the Gardens to Bed
Grade Four
Lesson Summary
When to use this lesson
Use this lesson in the fall when the garden beds are being cleaned and composted.
Objective
Students understand how the process of decomposition impacts the Earth’s surface.
Materials
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Shovels
Buckets for weeds
Buckets for compost
Compost thermometer
Estimated Duration
30 minutes
Ohio Curriculum Connections
Life Science
Changes in an organism’s environment are sometimes beneficial to its survival and sometimes
harmful.
 Ecosystems can change gradually or dramatically. When the environment changes, some
plants and animals survive and reproduce and others die or move to new locations. An
animal’s patterns of behavior are related to the environment. This includes the kinds and
numbers of other organisms present, the availability of food and resources, and the physical
attributes of the environment.
Social Studies – Geography

Human Environmental Interaction C9: Identify ways that people have affected the physical
environment of Ohio including use of wetlands; use of forests; building farms, towns, and
transportation systems; using fertilizers, herbicides, and pesticides; building dams.

Review with students why we compost. We compost to:
√ improve soil
√ control weeds
√ add nutrients
√ attract organisms that help decomposition
√ provide pore spaces for water, air, animals, and roots
√ reduce soil compaction from having too much of the mineral part (sand, silt, and clay) of
soil.
About Compost
Revised 10/15 © 2014 – 2015 Granny's Garden School, Inc. We encourage you to use these lesson plans and change
them to fit your specific needs. We ask only that you credit Granny's Garden School as your source.
Page 1
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Compare the flow of energy through an ecosystem to the flow of energy in a compost pile.
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How does energy flow through an ecosystem? An ecosystem is a community of living
organisms and nonliving substances (like air, rocks, water, and soil) that make up
environment.

What is the ultimate source of energy? The sun is the main source of energy on Earth. Earth
receives light and heat energy from the sun.

How do living organisms get energy? Organisms get energy from their food. Food chains
are the transfer of energy in a sequence from one organism to another

There are feeding levels in an ecosystem that consist of producers, consumers, and
decomposers.
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What are producers? Producers use a chemical process called photosynthesis to make their
own food to grow. Plants are producers.
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What are consumers? Consumers eat plants and/or animals. There are types of consumers
based on what they eat.
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What are herbivores? Herbivores only eat plants. Examples of herbivores are squirrels, deer,
cows, seed-eating birds, mice, rabbits, sheep, bees.
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What are omnivores? Omnivores are consumers that eat plants and animals. Examples of
omnivores are humans, chickens, raccoons, bears, pigs.
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What are carnivores? Carnivores are consumers that eat animals. Carnivores include
wolves, spiders, frogs, owls and other birds of prey.
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What are detritivores? Detritivores are consumers that eat dead and decaying plants and
animals.
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What are decomposers? Decomposers are consumers that eat organic matter and break it
down to inorganic matter. Decomposers are fungus and bacteria. They release basic
elements like carbon and nitrogen into air, water, and soil. These elements are important
nutrients for plant development.
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Along each level of a food chain, about 10% of available energy is transferred. Energy is not
recycled in this process. The end of the food chain is decay and the final feeding level is the
decomposers. Decomposers release inorganic compounds into the soil, which are the
nutrients used by producers. Most of the energy from decomposition is lost as heat.

Changes in the numbers of organisms in an ecosystem can affect the balance of the
ecosystem. Every link on a food chain is connected to at least two other links. If plants, the
producers, are lost, consumers must adapt, relocate, or die. If higher-level consumers are
lost, an organism lower in the chain becomes too abundant and disrupts the ecosystem.

These same categories are present in compost. The food chains in the compost pile
ultimately result in the chemical change of the original organic material to compost and the
release of elements like carbon and nitrogen. Both are in the atmosphere and both are
important to the development of plants and animals. Carbon is part of photosynthesis.

Examine some compost during your discussion by using a wheelbarrow filled with compost or
standing along the compost pile. Examine the wood chips that are used in paths. Compare
textures of both and discuss how the compost and wood chips are suited to the jobs we
Revised 10/15 © 2014 – 2015 Granny's Garden School, Inc. We encourage you to use these lesson plans and change
them to fit your specific needs. We ask only that you credit Granny's Garden School as your source.
Page 2
have given them. Discuss how their texture benefits their purpose – why wood chips go in
the path and compost in the beds.
 Compost – crumbly, spongy, holds water, nutrients released as it breaks down, porous for
seeds, plant roots, animals and to hold air and water
 Wood chips – chunky, heavy, bigger pore spaces for faster drainage, takes longer to
break down, chokes plant growth when a thick layer is used.

If you are by the piles of compost and wood chips, take the temperature of the air,
compost, and wood chips. Decomposition results in heat energy being released. Heat
comes from microorganisms, like bacteria and fungus, eating organic material. You can’t
see bacteria in the compost pile, but if you could line up 10,000 bacteria side-by-side, they
would equal one inch.

The right temperature is important in a compost pile. It is an indicator that the conditions are
right for the organisms to live in the compost pile. An active compost pile typically
generates heat in the range of 90 to 140 degrees. Heat helps composting to increase until
the temperature is above 140 degrees. Then, microorganisms start to die and the
temperature decreases to a level that supports their growth.

What if the compost pile is cold? There may not be enough oxygen for the microorganisms
to live. Particles may be too close together. There may be too much moisture. Perhaps the
pile reached a temperature that killed microorganisms. As the temperature cools to the
right range, microorganisms will grow again.
Composting Beds

Demonstrate the safe way to handle the shovel. The point is always down.

Half of the class will dig troughs in designated beds. Students should dig about a foot deep.
The soil should stay in the bed as much as possible. The removed soil will be used to bury the
plants pulled from beds.

Half of the class will remove plants and weeds from the beds. Weeds go in buckets and
other plants will be buried in troughs being dug by the other half of the class. Plants for
burying are placed in the trough and completely covered with soil by the diggers. The
buckets of weeds are dumped in designated areas. The empty buckets are placed by the
second bed.
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Students switch jobs to clear the second bed.
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Then students add compost to the top of their beds by collecting compost from the
compost pile.
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Students may not climb the compost pile. Find the best location that does not have a lot of
undecomposed leaves.
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Students collect a shovel and scoop compost into a bucket from the bottom of the pile.
Provide assistance as needed to start the process. Once a student has filled his/her bucket,
the shovel is returned to the storage bin.
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If you only have enough shovels for half of your class to scoop compost, half of the class uses
shovels to scoop compost into buckets. The other half pours compost into one bed.
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Students switch jobs to compost the second bed.
Sources
Revised 10/15 © 2014 – 2015 Granny's Garden School, Inc. We encourage you to use these lesson plans and change
them to fit your specific needs. We ask only that you credit Granny's Garden School as your source.
Page 3
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“Food Webs – How It Works”, Science Clarified,
http://www.scienceclarified.com/everyday/Real-Life-Physics-Vol-3-Biology-Vol-1/Food-WebsHow-it-works.html, 06-03-11.
Volkwyn, Roy. “Trophic Levels”, The Department of Biodiversity and Conservation Ecology,
The University of the Western Cape, 05-11-2006.
http://www.botany.uwc.ac.za/sci_ed/grade10/ecology/trophics/troph.htm, 10-06-2013.
“What is the Ecodome?”, Qualitative Reasoning Group Northwestern University,
http://www.qrg.northwestern.edu/projects/marssim/simhtml/info/whats-ecodome.html, 1006-2013.
“Food Web”, National Geographic Education,
http://education.nationalgeographic.com/education/encyclopedia/foodweb/?ar_a=1&ar_r=3, 10-06-2013.
McShaffrey, Dave. “Environmental Biology – Ecosystems”, Biology Department, Marietta
College, 03-02-2006. http://www.marietta.edu/~biol/102/ecosystem.html, 10-06-2013.
Revised 10/15 © 2014 – 2015 Granny's Garden School, Inc. We encourage you to use these lesson plans and change
them to fit your specific needs. We ask only that you credit Granny's Garden School as your source.
Page 4
Growing the Future by Teaching Children in the Gardens
[email protected]
20 Miamiview Lane, Loveland, OH 45140
www.GrannysGardenSchool.org
513-324-2873
Putting the Gardens to Bed – Grade Four
Stewart Elementary
In science, students learn that ecosystems can change gradually or dramatically.
This week, we discussed the flow of energy through an ecosystem, why it’s important,
and what can disrupt it. We learned that the nutrients needed in soil are the result of
the final feeding level of food chains in the ecosystem. Ask your student about the
three main groups of organisms in a food chain.
This week, we discussed why we add compost to our garden beds. Following our
discussion, students readied their class garden beds for winter by clearing and
composting spent plants and adding compost.
Email [email protected] to join our next gardening experience!
Revised 10/15 © 2014 – 2015 Granny's Garden School, Inc. We encourage you to use these lesson plans and change
them to fit your specific needs. We ask only that you credit Granny's Garden School as your source.
Page 5