About the Compost


Often referred to as "spent mushroom substrate" (SMS), Mushroom Compost is the composted result of a rich growth medium for mushrooms. It is made from agricultural materials, such as straw, straw horse bedding, cottonseed meal, nut shells, and gypsum. Sphagnum peat moss adds to the organic nature of the substrate, providing a consistent, formulated and homogeneous product.


After the mushrooms are harvested, the Mushroom Compost is steam treated prior to removal to eliminate any pest, pathogens and weed seeds resulting in a PDA accepted fertilizer product. Mushroom compost has high water and nutrient holding capacity and exhibits no nitrogen draw down problems. As a fertilizer and organic soil amendment, Mushroom Compost supports plant growth in a variety of applications to the lawn and landscape and inhibits Artillery Fungus.


Our mushrooms are Pesticide FREE and USDA Certified Organic (by External link opens in new tab or windowWhere Food Comes From Organic Inc). However, our compost is not certified USDA Organic, but we use all organic materials for our mushroom growing; zero pesticides.