Mushroom Compost is a growing medium that results from the mushroom growing process. Mushroom compost is made from agricultural materials, such as hay, straw, straw horse bedding, poultry litter, cottonseed meal, cocoa shells, and gypsum. Sphagnum peat moss adds the organic nature of the substrate, providing a consistent, formulated and homogeneous product. It is best used as a fertilizer and soil amendment for lawns, gardening and landscaping. Supports plant growth and inhibits artillery fungus.