Substrates

In mushroom cultivation, "substrates" refers generally to materials used as a growing medium for the mushrooms. These materials provide the nutrients and support necessary for mushroom growth. While substrate encompasses the entirety of the growing medium, many cultivators commonly refer to "substrate" as the non-nutritive part of the growing medium which is primarily responsible for holding water, providing aeration and structure; and rely on grains to provide the majority of nutrients necessary for growth.

Commonly used substrates include straw, sawdust, corn cobs, cottonseed hulls, and various types of agricultural waste, such as wheat and rice bran. The choice of substrate depends on the type of mushroom being grown, as well as the availability and cost of the substrate.

The substrate is typically sterilized or pasteurized to eliminate any competing organisms and to provide a sterile environment for the mushroom spawn to grow. After sterilization, the substrate is inoculated with mushroom spawn, and the mycelium (the vegetative part of the fungus) colonizes the substrate, eventually forming mushrooms.

Commonly used Grains
Rye Grain Sorghum Milo Whole Wheat Oats Wild Bird Seed

Commonly used Substrates
Compost Coco Coir Peat Moss Straw Sawdust Vermiculite Perlite