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History, Composting On Any Scale, Materials To Compost, How It Works, The Chemical Process

Composting is the process of arranging and manipulating organic wastes so that they are gradually broken down, or decomposed, by soil microorganisms and animals. The resulting product is a black, earthy-smelling, nutritious, crumbly mixture called compost or humus. Compost is usually mixed with other soil to improve the soil's structural quality and to add nutrients for plant growth. Composting and the use of compost in gardening are important activities of gardeners who prefer not to use synthetic fertilizers.

Nature itself composts materials by continually recycling nutrients from dead organic matter. Living things take in inorganic nutrients to grow. They give off waste, die, and decompose. The nutrients contained in the plant or animal body become available in soil for plants to take up again. Composting takes advantage of this natural process of decomposition, usually speeding up the process, by the creation of a special pile of organic materials called a compost heap.

The major benefit of compost is its organic content. Humus added to soil changes its structure, its ability to hold oxygen and water, and its capacity to adsorb certain nutrient ions. It improves soils that are too sandy to hold water or contain too much clay to allow oxygen to penetrate. Compost also adds some mineral nutrients to the soil. Depending on the organic material of the compost and microorganisms present, it can also balance the pH of an acidic or alkaline soil.

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