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Fall Activities:
Soil: Gotta Have It!

Soil...

Dirt...

What's the difference?

On the surface, they may look the same. However, there is a big difference. Figure out which one you want to have in your garden.

Soil is alive. Good soil is constantly changing and nurturing the plants that grow in it.
Dirt is dead. It doesn't change, and it cannot support life.
Good soil has bacteria, worms, animal manure, organic matter from dead plants, natural chemicals such as nitrogen, and fine-grained dirt.
Dirt has few or no nutrients, and possibly stones or big rocks.
In a way, soil breathes. The respiration of animals, bacteria, and fungi in the soil produces ten times more carbon dioxide each year than the amount of carbon dioxide released by all the things human beings do, including burning fossil fuels. Some of this carbon dioxide is used by green plants during photosynthesis. When these plants die, they return to the soil to be decomposed by soil organisms and the carbon of which the plants are composed again enters the carbon/carbon dioxide cycle.
Good soil contains humus (or decomposing plants). Humus makes soil dark and crumbly, and gives it an "earthy" smell. Bacteria, worms, and fungi put nutrients into the soil in a much gentler way than chemical fertilizers do.

After you decide where your plot will be located, take a soil sample and send it to a county agricultural extension service for analysis. Save the results for comparison with a spring sample. Your county agricultural agent may be willing to come to your school to discuss the soil results with the class.

Soil testing kits are available in hardware stores, too.

Don't throw away that garbage! Save it for your garden!

Regardless of where you will put your garden, the soil will benefit from added nutrients. Peruvian farmers used to restore their land by using natural fertilizers. They found that guano, the droppings of seabirds, worked best. In fact, it became an extremely prized resource! Peruvians also buried heads of anchovy fish in the ground when they planted crops in order to fertilize the soil!

You, too, can use natural fertilizers in your garden. Begin saving snack and lunch scraps. You can decompose them and add them to your garden. Any food items that have not been cooked and do not have animal fat in them can be safely added to your compost pile. (If you are not sure, ask your teacher or parent.) If you want to add to the compost pile, you have to eat healthy, fresh foods! Orange peels, apple cores, carrot peels, egg shells, corn husks, etc., all make great compost.

Compost

Compost is a natural fertilizer that is made by the process of decomposition, or rotting, of organic materials such as lawn and garden clippings and food scraps. Bacteria and fungi that are in the air, the soil, and on the organic material feed on it. In the process, the organisms release a variety of nutrients such as nitrogen and phosphorous that you can use to fertilize your garden.

Organic materials decompose at different rates depending on their size, their composition (what they are made of), the air and moisture in the soil, and the soil temperature. A lettuce leaf or banana peel, for instance, will rot much faster than wood chips or sheets of newspaper. In order for materials to decompose, they need oxygen (air) and moisture. (That's why garbage buried in landfills takes years to decompose.) Organic materials decompose more rapidly in warm temperatures than in cold temperatures. (That's why you refrigerate food to keep it from spoiling.) Composting is a good way for you to see how the food you eat can be recycled to help produce food from your garden.

[Compost container diagram]

To make a classroom compost container, take two 2 liter plastic soda bottles with caps, a razor blade, a small, sharp knife, scissors, a nylon stocking, waterproof tape, a rubber band, water, and food scraps.
Cut one bottle, "A," across its shoulders and across the base. Cut a second bottle, "B," about two inches below its shoulders and leave its base attached. Use a razor blade to start the cut and finish with a pair of scissors.
Wrap a piece of nylon stocking or netting around the neck of bottle B (the cap should be removed), and secure it with a rubber band.
Invert the top portion of bottle B and place it inside the base of bottle B. Tape the two parts together. Place the middle part of bottle A inside the inverted portion of bottle B. Next, add the remaining part of bottle A and make a hinge with a piece of tape. Leave the cap on the bottle.
With the point of a sharp knife, punch 10-12 small air holes into the compost bottle you have assembled.
Lift the "hinge" and add organic materials to the bottle along with just enough water to moisten the materials. No water should drain through the netting.
Periodically add water or recycle the water that drips through the netting.
Observe changes in the temperature, color, texture, and volume of the materials.
When the compost is dark and crumbly, it is ready to use. You can purchase a compost bin at any hardware store. Many local hardware stores will be willing to give discounts or grants if they know it is being used for educational purposes. Follow directions on your compost kit to make a great mulch pile.
Fall is a good time to start a compost heap near the proposed garden site. A compost pile started in the fall should be ready to use by spring planting time.

Book to Read:
Compost Critters. Bianca Lavies, Dutton Children's Books, 1993.

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Fall Activities: Soil: Gotta Have It!

Fall Activities:
Soil: Gotta Have It!