It is the same natural process that produces the dark humus layer on the forest floor. Composting differs only in the intentional creation of conditions that result in more rapid decomposition of organic material than what would normally occur in nature. For centuries composting has been a common practice for disposing of organic residuals while, at the same time, producing a useful product. Modern composting differs only in the application of scientific knowledge and technology to promote more rapid decomposition and better control of the final product in an environmentally sensitive way. Compost can be valuable in enhancing soil physical and chemical properties.
Compost contains small amounts of important plant nutrients and many micronutrients.
Addition of compost to soil can improve soil tilth and fertility. Compost is free of objectionable odors and stores and handles well. Properly processed compost is free of most pathogens and weed seeds. Compost has been shown to suppress certain soilborne diseases and can be used as a mulch to reduce weed growth. Just about any plant or animal material can be composted.