SunGro Horticulture Sunshine Coarse Perlite #4, 4 cu ftSunshine Perlite has a wide range of applications that will always be in demand. Clean and lightweight, this material can be used from propagation to finished production. Used to improve the drainage and aeration of growing media, Sunshine Perlite is a porous, lightweight, expanded volcanic rock. Its high porosity makes it a good aggregate in potting and germination mixes.