Organic soil management is the key to soil fertility. The basis of sustainable agricultural practices is good topsoil. Healthy soils grow healthy food. Soil is kept healthy by the addition of organic matter such as compost. Compost can be easily made at home. Many cities provide free backyard composting information.
Good soil has been identified by the National Sustainable Agricultural Information Service as having these characteristics: soaks up water easily, is crumbly to the touch, resists erosion and nutrient loss, stores moisture for drought periods, does not require increasing input for high yields, and produces healthy, high-quality crops. Other sources identify organic soil as having 20 to 30 percent organic matter.
Organic soil is a living community rather than an inert substance. Fertile soil feeds and sustains plant life. There are earthworms, fungi, protozoa, small mammals, bacteria and small algae in good soil. These microorganisms reproduce constantly, providing nutrients for the crops that grow in the soil. Keeping soil alive with microorganisms is the goal of organic soil management. Farm soil that is not fed and managed organically eventually becomes gray and lifeless and produces low-quality food.
Adding organic matter to soil is the most important feature of soil improvement. Organic matter in soil decomposes naturally through the growing cycle and must be put back in. The decomposition rate should not exceed the rate of addition of organic matter. A management program for soil fertility includes regular additions of composted natural materials.
Backyard composting is the easiest and least expensive way to manage the fertility of garden soil. Methods of home composting include bins, worm composting, food digesters and burying food scraps. Organic compost added to garden soil helps sandy soil improve water retention; helps clay soil to aerate; and increases microorganism growth in all soils. Compost is also used as a mulch to keep weeds under control and help save water.
Fertile soil is full of microorganisms that have four requirements to reproduce and create more fertile soil. They are carbon, nitrogen, oxygen and moisture. These elements can be included in a recipe to create organic compost. Nitrogen materials are the "greens" (yard clippings, kitchen cuttings and grass). Carbon materials are the "browns" (newspapers, dead leaves and straw). Oxygen is incorporated into the compost by turning the compost pile. Moisture is provided by keeping the compost pile moist.