Best Ever Compost
(Adapted from Composting: Wastes to Resources,
Cornell Waste Management Institute)
 
GRADE LEVELS: 4-6
 
SUBJECT AREAS: science, technology
 
CONCEPT: Composting turns organic wastes into a valuable product.
 
OBJECTIVE: To learn about composting.

MATERIALS:
Kitchen Compost
Add a mixture of some or all of the following ingredients:
  -vegetable peels and seeds
  -fruit peels and seeds
  -coffee grounds
  -eggs shells
  -nut shells
  -any other vegetable or fruit scraps
Note: Do not add meat scraps, bones, dairy products, oil, or fat. They may attract pest animals.

Yard or Garden Compost
Add a mixture of some or all of the following ingredients:
  - hay or straw
  - grass clippings
  - leaves
  - ashes
  - sawdust
  - wood chips
  - weeds and other garden waste
  - manure
  - shredded paper
 
KEYWORDS: compost, biodegradation
 
BACKGROUND: Composting is nature's way of recycling. Decomposition will occur whether we help it or not. But since we produce so much waste we get paid back when we help to speed up the composting process. Composted material improves our gardens.
 
Composting is like baking a cake. Simply add the ingredients, stir, "bake," and out comes -- compost!
 
Whether you compost kitchen wastes or yard and garden wastes, there are a few basic steps to follow. Here are the necessary ingredients and general directions for composting.
 
PROCEDURE:
 
1. Choose a container for making your compost. Any type of composting bin will do (chicken wire enclosure, wooden box, etc.).

2. Place kitchen or yard wastes into the composting bin. Chop or shred the organic materials if you want them to compost quickly.
 
3. Spread soil or "already done" compost over the compost pile. This layer contains the microorganisms and soil animals that do the work of making the compost. It also helps keep the surface moist. The pile should be about 4 cubic feet in size.
 
4. Adjust the moisture in your compost pile. Add dry straw or sawdust to soggy materials, or add water to a pile that is too dry. The materials should be damp to the touch, but not wet that drops come out when you squeeze it.
 
5. Allow the pile to "bake". It should heat up quickly and reach the desired temperature (90 to 140 degree F, or 32 to 60 degree F) in four to five days.
 
6. "Stir" your compost as it bakes by turning it with a pitch fork or shovel if you want to speed up the baking time.
 
7. The pile will settle down from its original height. This is a good sign that the compost is baking properly.
 
8. If you mix or turn your compost pile every week, it should be "done", or ready to use, in one to two months. If you don't turn it, the compost should be ready in about six to twelve months.
 
9. Your "best ever compost" should look like dark crumbly soil mixed with small pieces of organic material. It should have a sweet, earthly smell.
 
10. Feed compost to hungry plants by mixing it with the soil.
 
FOLLOW-UP:
Try growing a few beans or other seeds in pots, some filled with sand and others filled with a mixture of sand and compost. Compare how well the seedlings grow. Discuss the plants' need for nutrients and water. Sand is a poor nutrient source and does not store water. When compost is mixed in, both of these needs are better met. Gardeners can similarly enrich their gardens using compost.
 
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