Specialized substrate is a key ingredient in mushroom production. The preparation of substrate is a process that converts plant and animal products into a mixture of decayed organic matter that is necessary for growing mushrooms. The substrate is made from other agricultural materials, such as hay, straw, straw horse bedding, poultry litter, cottonseed meal, cocoa shells and gypsum.  Without this special substrate, mushrooms will not grow. 

The process is technical and scientific but mushroom substrate prepared on the farm has only one use – to grow mushrooms. Just as soil is the growing medium for field crop production, substrate is the growing mix for mushroom production. For all crops, including mushrooms, the right ingredients must be blended to create a quality product.