The Grey Line is the most versatile of the root pouches, and is semi-degradable. Can be used for in-ground production, pot-in-pot or above ground. When used in-ground, the natural fibers draw water from surrounding soil. When used for pot-in-pot, the pouches prevent roots from penetrating fabric because it prunes by entrapment rather than air pruning. When used above ground, roots are still pruned. Used by both outdoor and indoor growers, for horticulture or hydroponics because it has the tensel strength to hold up to the elements but the natural fiber blended in to offer thermal and moisture control. Provides excellent drainage and root pruning. Made from a PET & natural fiber blend. Recommended for can-yard, in-ground, pot-in-pot, CEA, or greenhouses. Semi-degradable, 3-4 seasons.