Composting is the controlled decomposition of organic materials using aerobic bacteria. By composting, you return organic matter to the soil in a usable form. The composting process reduces material volume by 70-80%. Organic material in the soil improves plant growth by:
- Enhancing soil texture
- Adding nutrients back into the soil
- Increasing the soil's ability to retain water and nutrients
- Improving soil structure by the addition of organic matter
- Loosening heavy soils, allowing better root penetration
- Reducing the need for fertilizers
Mixing green and brown plant materials together is the basic rule of composting. Green materials (i.e. grass clippings) supply nitrogen. Brown materials (i.e. dead leaves) are high in carbon. Moisture and air are also needed for the composting process.
Construct your compost pile directly on the soil to allow contact with microorganisms. A partly shaded location works best; too much sun will dry out the pile. Larger piles will retain more heat and decompose faster.
As the yard materials go through the composting process, there is an increase in temperature within the compost pile. High temperatures kill most disease pathogens that are present. Weed seeds and pesticides are destroyed as well because of the high temperatures.
After a few weeks, the pile will be ready to turn. Turning and mixing the pile with a pitch fork or shovel provides the oxygen necessary for decomposition and compensates for excess moisture.
Materials that may be acidic when added to a compost pile will become almost neutral in pH. Compost acts as a buffer against high or low pH when added to soil that is acidic or alkaline.
A compost pile started in late spring can be ready for use in the fall. Start another pile in autumn for use in the spring.
Compost bins can be useful to enclose and manage your compost pile. Bins can be built from wood, cinder blocks, chicken wire, or snow fencing. The following are links to help you get started.
University of Illinois
Basics of Home Composting
University of Illinois Extension
U.S. Environmental Protection Agency
Additional Composting Information