Mushroom composting

Mushroom compost is a dark, crumbly material. It is the growing medium for commercially cultivated mushrooms, which having been used once is discarded because mushrooms are extremely vulnerable to soil-borne diseases and each crop is grown on fresh, sterilized compost. It is good for improving the texture of the soil but as it contains lime it is more suitable for use on acid soils. Spent mushroom compost usually contains residues of chemicals as well as the fungus gnats they are used to destroy, so it is best to let it stand for 12 months before use.