Perlite is a very versatile material that can be used in a variety of applications. Perlite is an excellent air-entraining additive and can be used in place of coarser media, such as vermiculite or peat moss, to enhance the ability of plants to hold water. It is also an excellent carrier for fertilizer, and can be added to soil to help make it more friable and improve drainage.
Perlite has also been used as a soil amendment to replace sand or clay, but this application is not recommended due to its tendency to form clods which may interfere with plant growth. Perlite is typically used in a two-step process. First, a layer of Perlite is applied to the soil surface using a spreader box. The Perlite is then tamped down with a roller to a depth of one-half inch or more.
Perlite can also be used to cover large areas of bare soil. For example, it can be mixed with peat moss and used to cover a new lawn. The use of Perlite in agriculture has been studied in some detail. It has been found that Perlite improves the water retention capacity of soil, but it does not appear to improve the water holding capacity.