What is Mushroom Compost?

Often referred to as Spent Mushroom Substrate (SMS), Mushroom Compost is the 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 to the organic nature of the substrate, providing a consistent, formulated and homogeneous product.

After mushrooms are harvested, the Mushroom Compost is steam treated prior to removal to eliminate any pest, pathogens and weed seeds resulting in a Pennsylvania Department of Agriculture accepted fertilizer product.

• Mushroom Compost has high water and nutrient holding capacity and exhibits no nitrogen draw down problems.
• As a fertilizer and soil amendment for farming, Mushroom Compost supports plant growth in a variety of plant applications such as corn, pumpkin, tomato and potato yields.
• Mushroom Compost supports plant growth of mulch hays from orchard grass, timothy, reed canary grass, tall fescue and brome grass.
• As a fertilizer and soil amendment for lawn care and landscaping, Mushroom Compost supports plant growth and inhibits artillery fungus.

See the Downloads page to download files containing more information on Mushroom Compost. See the FAQs page for answers to common questions on Mushroom Compost. For details on how to contact us, see the Contact page.

Web site produced with a grant from the Pennsylvania Department of Agriculture.