To incorporate an organic or mineral material such as compost, rock powder, sphragnum peat, fertilizer, or lime into the soil to enhance its fertility or structure, or adjust its pH.
Examples of Soil Amendments:
Compost:See definition of compost.
Aged Manure: This soil amendment is great for vegetable growers. It consists of composted animal manures (usually from farm animals) and possesses all of the qualities of good compost: high levels of organic matter, good nutrient- and water-holding potential, dark color, and no offensive smells.
Earthworms: Earthworms are beneficial for a number of reasons. As they tunnel through the soil, they create air pockets and space behind them, introducing better air and water movement into the soil. As they chew through leaf litter, their excrement (known as vermicompost) consists of round aggregates of soil particles held together by slime produced by bacteria in the worm's stomach. These round aggregates of soil are packed with organic matter and nutrients, all of which are immediately available for plants to use.
Green Sand: Green sand is a very useful soil amendment. Mined from marine deposits, it gets its color and name from its high amounts of potash (a source of potassium). It also helps loosen clay soils, and aids in water and nutrient retention. Green sand contains many trace elements as well. It works as a slow-release amendment, so a little bit goes a long way.
Mulches: There are many benefits of mulching. Mulch insulates the soil, protecting the plants from extreme temperatures. It prevents soil from eroding away with storm water or wind and conserves precious soil moisture that otherwise would evaporate. Types of mulch include pine-bark mini nuggets, pine-soil conditioner, pine needles, straw or hay, shredded cedar mulch, wood chips, composted leaves, and buckwheat hulls.