Wondering what to do with fallen leaves? Consider compost. Some people call it black gold, most call it by its proper name: compost. This material provides so many benefits to the soil that all gardeners should strongly consider its use. The addition of compost can improve the soils ability to store nutrients and water, improve water drainage and air movement, improves the soil structure, and more. Every soil can benefit from the addition of compost, but some soils become markedly improved by its addition, especially high clay soils.
Compost is a natural process of decay that changes organic wastes into valuable humus like material. Place any organic matter in your backyard (pile of leaves, cardboard box, watermelon rind) and they will eventually decompose. However, placing those organic products (and any others) into a pile and managing them properly will yield compost.
What types of materials should be placed in a compost pile? You'll need a carbon source, a nitrogen source, plus the proper mix of air and water. Carbon sources can be many and are varied and these include "brown" materials- dead plants, both vegetable and weeds, straw, all those plants that have quit bearing, plus leaves.
Nitrogen sources are anything green- grass clippings, green leafy wastes, fresh (green) plant material such as plants or weeds you've pulled, vegetable scraps from the table, etc. The ideal mix is 2 parts "green" to 1 part "brown". The smaller the pieces of material, the quicker the results. Try not to add any pieces larger than 1" square.
The size of the pile shouldn't be too large or too small. The ideal size is about one cubic yard. Too small and the temperatures won't remain stable and too large and getting air into the center of the pile becomes difficult. Temperature and moisture are essential for the bacteria that do the decomposting to survive. The pile should have the consistency of a damp sponge. Temperatures should range from about 110-150 degrees.
Once you've gotten the size required, do not add additional materials to the pile. Let it begin to work. Turn the pile often during the first several weeks (twice a week) this mixes the materials and adds air. Mix once a week for a couple more weeks, then every other week or so. Monitor the temperature and the moisture. In a properly constructed and managed pile, you'll have finished product in a few months. One not managed may take up to a year. If you notice odors from the pile, then it's time to get out the pitchfork and mix the product. Odors are caused by anaerobic (without oxygen) bacteria so get air mixed back into the system.