WORM CASTING POTTING SOIL, 20% WORM CASTINGS, 8 quarts 8 quarts of potting soil blended with 20% worm castings. INGREDIENTS-40% organic sphagnum peat moss, 40% organic perlite, and 20% of our Black Gold Worm Castings. Our potting soil blend is all natural and organic, no chemicals added. Our potting soil is ready for use, plant and add water.