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When should you use compost soil?

Compost is a material that can enhance any soil it's used on. Compost is usually made up of various types of organic waste, including manure, kitchen scraps and yard waste.

When using compost, you'll want to store it in bins and allow some time for the decomposition process to take place. The next step is to spread the compost all over your garden. Compost is doubly beneficial because not only is it nutrient-rich to begin with, but it actually becomes even more so as it continues to decompose (after it is spread). As a result, compost's effectiveness is much longer-lasting than that of fast-acting fertilizers and chemicals [source: Stell].

The use of compost benefits any type of soil. For example, compost serves to bind loose, sandy soil, as well as maintain nutrient and moisture levels. Silt, clay and other dense soils are also enhanced by being mixed with with compost. The reason for this is that by reducing compaction, compost causes more moisture and air to reach the plants' roots.

To derive the maximum benefit from compost, it's recommended that you combine it with topsoil layers. The ratio to remember is approximately six inches (15.2 centimeters) of compost to every 12 inches (30.5 centimeters) of topsoil [source: City of Bremerton]. If you live in an area that has particularly poor drainage, however, it's recommended that you use compost and commercial topsoil in equal parts, which would produce elevated planting beds. Such a setup would allow plants to grow more successfully, since any extra moisture would wind up below the roots.