OMRI certified. Vermicast is worm castings-the result of worms breaking down kitchen scraps, plant matter, and organic materials. Adding the rich nutrients of vermicast to any plant will greatly improve the soil with addition of compost. Vermicast includes plant growth stimulators and soil boosters which bind with soil particles. It is plant superfood. Mix in with soil, compost, seed rows, indoor potted plants, container gardens, as well as the root zone of any plant.