Fertilizer is defined as any substance, such as manure or nitrates, used to make soil more fertile. Organic fertilizers are derived from natural sources and synthetic fertilizers are created from chemical compounds. Compost–a fertilizer created from a wide range of natural materials–provides all the macro- and micronutrients needed for plant growth. “There are 17 essential nutrients that a plant needs to survive," says Jerry Goodspeed, Utah State University Extension horticulturist. "They are all important and necessary for growth and survival.” Different soil types absorb fertilizers differently.
Amend the Soil
Determine your soil type by holding a handful of it. If it clumps together tightly in a ball it is clay-like. If it runs quickly through your fingers, it is sandy soil. If it crumbles and falls loosely from your hand, it is balanced garden loam. Balanced soil clumps into small aggregates because there is a combination of organic matter, mineral content, water and oxygen.
Add one shovel-full of compost for each square foot of clay-like soil. The decomposed plant material in compost fertilizes clay soil and adds texture. Roots need textured soil to expand easily. Roots assist in the oxygen intake of soil. Clay soil can also be amended with sand, peat moss or wood bark. Compost fertilizer can be applied regularly as a side-dressing as plants grow or as an amendment in spring.
Add two shovel-fulls of compost fertilizer to each square foot of sandy soil. Sandy soil needs organic matter so it will hold plant life. The mineral content of sandy soil is high, but it cannot retain nutrients well. Synthetic fertilizers are not easily absorbed into sandy soil and can run into the ground water supply. Compost fertilizer does not burn delicate plant roots.
Re-check the soil yearly to assess its texture. Repeat Steps 2 and 3 if necessary. Add compost twice a year to help soil fertility.