Substrates for Mushroom Cultivation

Growing mushrooms is an interesting and productive hobby for gardeners both indoors and outdoors. Instead of planting seeds in the ground as with traditional gardening, growers use mycelium, a web-like material of mushroom spores, and special substrates for cultivation of particular kinds of mushrooms. Mushroom cultivation requires cool temperatures and shady conditions.

Substrates come in many different varieties, and it seems that mushroom growers are always discovering new types. Compost is the most traditional substrate used to grow mushrooms, but growers also use straw, logs, sawdust, paper products, garden debris, used coffee grounds and corn cobs, according to the Mushroom Shack website. Mushroom-growing experts often recommend certain types of substrate for particular kinds of mushrooms, but experimenting with substrates is part of the fun of growing your own mushrooms.

The common white button mushroom, Agaricus spp., grows on a number of substrates, including wheat straw, corncobs, horse manure, chicken manure and feather meal, according to University of Hawaii botanists. Mixtures of these types of substrates also provide a good growing media for white button mushrooms.

The shiitake mushroom, Lentinula edodes, is a wood-loving type that grows best on hardwoods like oak and ironwood. Other woods such as beech, alder, birch or sweetgum also make a good substrate for shiitake mushrooms. With shiitakes, substrates like corn cob, straw or combination substrates do not produce results as favorable as hardwood does.

Oyster mushrooms, Pleuratus spp., grow on a variety of substrates, including cereal straws, paper, corn cobs and coffee grounds. They can also grow on logs. The spawn is grown first on dowels, which are then inserted into the logs. Oyster mushrooms generally do not require sterilization of the substrate like other types of mushroom do. They will generally outgrow any contaminants in the medium, according to the Mushroom Company website. Oyster mushrooms will also grow on cocoa shell waste, cotton straw and paper substrates.

Maitake mushrooms, also called the hen of the woods or by its botanical name, Grifola frondosa, grows as a clump of overlapping mounds or interwoven mushroom leaves. Maitake prefer hardwoods as a growing medium and outdoor cultivation on logs. Indoors, hardwood sawdust or wood chips of oak, poplar, elm or alder will work for maitake mushroom cultivation.

Wine cap mushrooms, Stropharia rugosa-annulata, grow best on hardwood chips. Straw will also work, but it should be oat or wheat straw and not plain hay, which composts too quickly. Moisten the straw and mix it with layers of spawn in a shady outdoor bed. Mixing the straw with redwood, pine or cypress wood chips provides a good substrate for wine cap mushrooms.