Horticultural vermiculite has the excellent property of improving soil aeration while retaining the moisture and nutrients to feed roots, cuttings, and seeds for faster growth. In many horticultural applications, horticultural vermiculite is a critical component for the grower and the homeowner. Vermiculite is the name given to a naturally occurring hydrated laminar mineral similar to mica. Once the vermiculite is processed (exfoliated) it is sterile, odorless, non-toxic, and permanent. It has desirable horticultural characteristics, such as being lightweight, with a high capacity for moisture retention. It also holds and releases nutrients (high cation exchange capacity CEC). The color of vermiculite can range from light tan to a golden brown depending on the size and origin. It has a bulk density of four to six pounds per cubic foot. Each grade size has a particular specialized application in the horticultural industry.
