Impact Organics Earthworm Castings offer you the highest quality castings from pampered worms. These worms are fed only organic black humus and a proprietary organic worm food and live in an environment free of garbage, yard waste and manure. The end result, their castings, is an organically rich and powerful soil amendment and plant food. Whether you use these castings in their natural state or brew them into a tea, you will be giving your plant the tools it needs to thrive: boosted microbial life in the soil, which leads to improved soil structure and enhanced root development. Some of the nutrients present in IO Earthworm Castings are nitrogen, phosphorous, magnesium, potassium, calcium, copper, zinc, iron and manganese. These OMRI Certified earthworm castings are completely odor free and help avoid nitrogen burn on your plants.