How Is Fertile Soil Formed?

Life Cycle

• Fertile soil is soil that is capable of sustaining life. Young soils are oftentimes incapable of supporting life, because they lack nutrients and organic matter. They may also be highly porous -- meaning that water and nutrients drain too rapidly to be of use to developing plant life. Old soils may also be infertile, because their particle size is weathered and small, two factors that contribute to soil compaction. Fertile soils are usually in the middle of their life spans. They contain adequate amounts of organic matter and are capable of supporting both plant and animal life.

Compost

• Growers can speed along the fertility process and can also replenish soil fertility by managing their soil. Incorporating compost into topsoil is an inexpensive way to manage soil. Save kitchen scraps and disease-free garden debris for inclusion into a compost pile or heap. Kitchen scraps should be vegetative in nature and free of oils and fats. Turn your compost pile at least once every two weeks. As the organic matter begins to decompose, it starts smelling sweet and earthy. This matter is important to soil health and fertility, because it helps soil retain water and nutrients and also allows space for microbes to live and thrive. Microbes are responsible for breaking down matter into easy-to-consume nutrients that are readily accessible to plants. Annual applications of compost continually provide bulk, some nutrients and encourage microbial growth.

Manure

• Manure is an animal waste product that is high in nitrogen. When aged with compost, the resulting substance is capable of replenishing nitrogen-depleted soils. If added to to soil while fresh, manure has the potential to damage soil structure and young plants' root systems. This is because of the high concentration of nitrogen. Manure is a natural means of replenishing soil, but the results may be inconsistent. Some animal manures are higher in nitrogen than other manures. Nutrients are also lost during the aging process. Because of this inconsistency, some growers prefer to use manufactured fertilizers to help maintain their soil's fertility.

Commercial Fertilizers

• Fertile soil contains nitrogen, phosphorus and potassium -- three elements necessary to support plant life. Other elements, such as sulfur, magnesium, iron and copper, are also necessary but to lesser degrees. Commercial fertilizers are sold according to the amount of nutrients present in the mix. A 15-15-15 fertilizer is a fertilizer that contains 15 percent nitrogen, 15 percent phosphorus and 15 percent potassium. These numbers are more meaningful when used in conjunction with soil test results. Soil tests are available through local county extension offices and private companies. These tests determine the amount of nutrients present in soil. Fertilizer formulas are then recommended to growers, who can use the information to purchase the best fertilizer for their growing conditions.