From meaty portabellas to succulent shiitake to delicate enoki, mushroom are an important ingredient in many gourmet meals. Mushrooms have very precise requirements for light and moisture levels, and they are also particular about growing media. The beginner mushroom gardener will have the most success with purchasing a mushroom-growing kit, which can later be transferred outside to a create a permanent mushroom patch. Most mushrooms need a period of cold in the winter, so gardeners in tropical or desert locations may not be able to grow mushrooms outdoors.
Purchase a mushroom-growing kit, available from many garden centers, specialty gift catalogs or online. White button, portabella and oyster mushrooms are among the easiest mushrooms to grow; also consider shiitake, maitake and enokitake. Depending on the variety of mushroom, you may have to "cold-shock" the kit by submerging it in cold water or refrigerating it for a period to activate the mushroom spawn, but most mushroom kits simply require high humidity and indirect light. Your mushroom kit will come with specific instructions for its care.
Select a spot outdoors to transfer the spawn for when your indoor mushroom kit stops producing. The spawn may still be active, and if provided with the right environment may colonize and produce more mushrooms in about a year. Most mushrooms like shady locations, and a hardwood forest floor is ideal. You will probably only need an area of about 4 square feet, depending on how big your mushroom kit is.
Rake away the leaves and and remove any sod or weeds. Spread 1 inch of compost over the area.
Take apart your mushroom kit. The kit likely consists of a box or bag filled with sawdust, wood chips, straw or other substrate. Within the substrate there should be white masses, which are the mycelia, or root-like structures of mushrooms. Spread the substrate and mycelia over the prepared mushroom patch. You can include the box or bag, too, if it is made of biodegradable materials like cardboard or burlap.
Cover the mushroom patch with untreated hardwood chips or shredded bark. Oak, maple, poplar and elm are all good wood choices. You can also purchase additional mushroom spawn to give your mushroom patch a better chance of colonization.
Water your mushroom patch thoroughly, but do not allow it to become waterlogged. Keep your mushroom patch evenly moist throughout the spring, summer and fall. Your outdoor mushroom patch may begin producing more mushrooms within 9 to 12 months.