How to Grow Mushrooms Indoors

Alfred Vannappuram

Growing mushrooms at home is a task that any gardener interested in growing their own food should attempt. Mushrooms are a healthy addition to any diet, as they are low in calories and fat, high in fiber, and contain high amounts of potassium. In addition, they are very easy to grow at home. Mushrooms are best grown indoors where the temperature and light conditions can be more readily managed. Learning how to grow mushrooms indoors is a matter of managing their growing conditions carefully.

Steps

1
Decide what type of mushroom you want to grow. The 3 types of mushrooms that are easiest to grow at home are oyster, white button, and Shitake. The method for growing each mushroom is similar, but the ideal growing medium differs.
- Oyster mushrooms grow best in straw; Shitakes grow best on hardwood sawdust; button mushrooms grow best in composted manure. These different growing media reflect the different nutritional needs of each species. However, each of these 3 species can be grown readily enough in sawdust or straw.
- Choosing a type of mushroom to grow is a matter of taste. You should grow the type you most want to eat.
Ad
2
Purchase mushroom spawn. Mushroom spawn is sawdust permeated with mushroom mycelia - essentially the root structure of the fungus. It is used much like plant seedlings to facilitate growth. You can purchase mushroom spawn from several online retailers, some gardening supply stores, or some specialty organic living stores.
- Make sure to buy spawn rather than spores. Some retailers will also sell spores, which are more akin to the seeds of plants (rather than seedlings). Growing mushrooms from spores takes more time and practice, and is best suited for a seasoned mushroom grower.
3
Heat the growing medium to spread the mycelia into it. The mycelia in your mushroom spawn need to spread into the growing medium thoroughly before producing mushrooms. A warm temperature encourages this growth.
- After choosing the growing medium suited for your mushroom species, place a few handfuls of it into a baking pan. A shallow pan with a large surface area will provide the most room for your mushrooms to grow.
- Mix the spawn into the growing medium with your fingers. Place the baking pan on a heating pad set to 70 degrees Fahrenheit (21 degrees Celsius). This is the ideal temperature to encourage growth.
- Leave the setup in a dark environment, such as a cabinet, for about 3 weeks. This will allow the mushroom mycelia to permeate the growing medium.
4
Place the growing medium into the proper environment. After 3 weeks, you need to place the pan into an environment that is dark and cool (about 55 degrees Fahrenheit / 13 degrees Celsius). A basement usually works well for this, but a cabinet or drawer in an unheated room will work in winter.
- Cover the growing medium with a handful of potting soil and spray the entire mixture with enough water to dampen it thoroughly. You can place a damp towel over the pan to prevent moisture loss if desired.
- The mix should be kept moist and cool as the mushrooms grow. Check it periodically and spray it with water as necessary.
5
Harvest your mushrooms when they are fully grown. In about 3 weeks, you should see small mushrooms appearing. Continue to keep their environment moist, cool, and dark to encourage their growth. When their caps separate fully from their stems, they are ready to harvest. You can simply pluck them with your fingers; it is best to rinse them before cooking or

eating.
How Mushrooms Grow
Mushrooms grow from spores -- not seeds -- that are so tiny you can't see individual spores with the naked eye.

Because the spores don't contain chlorophyll to begin germinating (as seeds do), they rely on substances such as sawdust, grain, wooden plugs, straw, wood chips, or liquid for nourishment. A blend of the spores and these nutrients is called spawn. Spawn performs a bit like the starter needed to make sourdough bread.

The spawn supports the growth of mushrooms' tiny, white, threadlike roots, called mycelium. The mycelium grows first, before anything that resembles a mushroom pushes through the growing medium.

The spawn itself could grow mushrooms, but you'll get a lot better mushroom harvest when the spawn is applied to a substrate, or growing medium. Depending on the mushroom type, the substrate might be straw, cardboard, logs, wood chips, or compost with a blend of materials such as straw, corncobs, cotton and cocoa seed hulls, gypsum, and nitrogen supplements.

Where to Grow Mushrooms
Mushrooms prefer dark, cool, moist, and humid growing environments. In a house, a basement is often ideal, but a spot under the sink may be all you need.

Test the proposed location by checking the temperature. Most mushrooms grow best in temperatures between 55 and 60 degrees F, away from drying, direct heat and drafts. Enoki mushrooms prefer cooler temperatures, about 45 degrees F. Many basements are too warm in summer to grow mushrooms, so you might consider growing mushrooms as a winter project.

Mushrooms can tolerate some light, but the spot you choose should stay relatively dark or in low light.

Some mushroom types grow outdoors in prepared ground or logs, a process that takes much longer (six months to three years) than in controlled environments inside.

Types of Mushrooms to Grow
There are many kinds of mushrooms. One of the beauties of growing your own instead of wild-harvesting them is that you can be sure you're not picking a poisonous mushroom.

These mushrooms are the types most commonly grown at home:
Crimini
Enoki
Maitake
Portobello
Oyster
Shiitake
White button

Each type has specific growing needs. Grow white button mushrooms on composted manure, shiitakes on wood or hardwood sawdust, and oyster mushrooms on straw, for example.

Growing Mushrooms
If you are growing mushrooms in your home, you have a couple of options for materials.

You can buy mushroom kits already packed with a growing medium that's inoculated with mushroom spawn. Buying a kit is a good way to begin your knowledge of mushroom growing. If you start without a kit, the type of mushroom you choose to grow determines the substrate you grow the mushrooms on. Research each mushroom's needs.

Button mushrooms are among the easiest types to grow. Follow Kansas State University's directions for growing button mushrooms. Use 14x16-inch trays about 6 inches deep that resemble seed flats. Fill the trays with the mushroom compost material and inoculate with spawn.

Use a heating pad to raise the soil temperature to about 70 degrees F for about three weeks or until you see the mycelium -- the tiny, threadlike roots. At this point, drop the temperature to 55 to 60 degrees F. Cover the spawn with an inch or so of potting soil.

Keep the soil moist by spritzing it with water and covering it with a damp cloth that you can spritz with water as it dries.

Button mushrooms should appear within three to four weeks. Harvest them when the caps open and the stalk can be cut with a sharp knife from the stem. Avoid pulling up the mushrooms, or you risk damage to surrounding fungi that are still developing. Harvesting every day should result in a continuous crop for about six months.