KRUM Horticultural Perlite is a specially processed, unique volcanic mineral with a long and enviable record of performance as a propagating and growing medium. Each white granule is comprised of tiny closed air cells or bubbles which account for KRUM's light weight, reflectivity, adsorptive capability, and superior insulating qualities. The surface of each granule is covered with tiny cavities providing a large surface area capable of retaining water, air, and nutrients. This physical structure makes KRUM Horticultural Perlite an ideal growing medium, providing optimum air-water relationships for efficient plant growth. KRUM is available in various gradations suitable for specific horticultural applications. >>Details