WORM·HUMUS is high-quality, 100% organic compost. It can be used to refresh All-Mix®, be added to substrate mixtures already in use, or to prepare the garden subsoil. Our 100% pure, organic worm castings are lab-tested and to ensure the very highest quality they have has not been produced using any farm yard waste, landfill waste or compost. No manure from horses, cows or other grazing animals has been used in its production. The diet fed to the worms includes high quality mineral rock dust and it is highly controlled. These characteristics, combined with the natural soil microbes the casting contains, make the highest standards for worm castings achievable.