SunGro Horticulture Sunshine Perlite #3, 4 cu ftWhite perlite granules are the result of the expansion of combined water vaporizing in the crude mineral and forming enclosed air pockets. Because of the great quantity of air in these pockets, the product is very light and has excellent physical qualities for use in plant propagation. The physical properties of the product also further enhance its use in horticulture. It is inert, sterile, safe to handle and has no odor.