Growing Mushrooms at Home

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These budding caps will mature into a harvestable crop of oyster mushrooms.
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These oyster mushrooms will continue to produce “crops” of mushrooms over the next few years, if the logs are kept moist.
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Oyster mushrooms make a tasty addition to any recipe calling for mushrooms.
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The author’s son daps wax onto the sawdust-covered inoculation holes in the fresh oak nursery logs.

Fresh tomatoes, healthy green beans, sweet potatoes — these are all good edibles that make “growing your own” a positive and nutritious experience. But what about fresh, homegrown mushrooms? Shiitakes, oysters — even morels?

Believe it or not, with a few purchased tools, some freshly cut logs and a little patience, you can easily grow fresh mushrooms at home, either to sell for a profit, or to enjoy them yourself.

The easiest way to grow mushrooms at home is to order “spawn” from a reputable online company. Spawn is a big loaf of moistened sawdust knitted together with mycelium — the vegetative tissue of the fungus, similar to the root system of a perennial plant.

In March 2009, our son Robbie ordered his first mushroom spawn from Field and Forest Products, a great company in Wisconsin with a knowledgeable staff and lots of spawn choices suited for various climates and conditions. Robbie chose to grow a variety of shiitakes called Native Harvest, and Grey Dove oyster mushrooms. He ordered about $150 worth of supplies — two 51/2 pound packages of spawn; a special tool for thumping the spawn into small holes drilled into fresh oak logs; cheese wax to seal the holes to prevent moisture, stray mold or fungal spores from invading; and an educational book with all the information needed to successfully propagate, harvest and sell homegrown mushrooms.

Shortly after Robbie’s order arrived in early April, our weather turned sunny and cool, and temperatures climbed to the 60s — perfect for getting out a chainsaw and cutting a big pile of oak and maple logs. (Most mushroom supply companies sell logs, too.) There are a variety of ways to grow mushrooms, but log cultivation imitates nature most closely. It is also low-cost (albeit physically demanding). The logs used must be live and healthy, and it’s best to cut the nursery (spawning) logs in spring before the leaves emerge. The instructions suggest cutting 3- to 8-inch-diameter logs about 3 feet long. After they are cut, the logs should be inoculated with the spawn right away, before they start to dry out or become contaminated with competing organisms.

Soon after we cut the logs, we set up a lab on our picnic table with an old two-burner hot plate, a Folgers’s coffee-can “kettle” with my expensive candy thermometer clipped to the side (half-submerged in melting wax), and a nearby pile of waiting logs. Robbie carefully sealed the spawn in with hot wax, after having punched it into small holes drilled in diamond-patterned rows, just as the instructions specified. The purpose of daubing wax over each spawn-filled hole is to protect it from moisture loss and bacteria infiltration.

Finally, loading the logs into the bed of the farm truck, Robbie hauled them out back and soaked them with the garden hose. He stacked them in neat rows in the corral, which is shaded by our 100-year-old barn and protected from wind and sun — two of mushroom growers’ worst enemies because the logs must remain damp. A grower can purchase optional “fruiting blankets” to cover and protect inoculated logs from the elements and to increase the humidity that sprouting mushrooms love.

According to all the information we’ve read, mushroom farming is an unpredictable business. There are so many weather-related variables — temperature, humidity, rainfall, sun, shade, etc. The book from Field and Forest Products says to incubate logs in a shady spot for six to 18 months to allow the spawn to colonize the logs fully.

The first weeks of July were exciting ones, as we were able to see the first buds of the early oyster variety bubble up and quickly spread into perfect layers of pale gray, finely gilled, picture-perfect mushrooms. At the end of August, Robbie brought in a little brown lunch sack of fresh, immaculate oyster mushrooms! He fried some in butter and made an Asian omelet, adding cashews, onions and soy sauce. It was beautiful and delicious. After that, small flushes of oyster mushrooms continued to surprise us. Now we have several freezer bags of clean, neatly sliced mushrooms stacked in our freezer for later use.

We are patiently waiting for the excitement of watching the shiitake logs sprout for the first time, and to see the oysters produce yet again.

Each 40-inch log should produce 2 to 4 pounds of mushrooms in about 12 “flushes” (crops) over the few seasons it bears. Each flush will average a quarter to a third of a pound before becoming, as the book says, “fully spent.”

Have you grown culinary mushrooms? If so, tell us about your successes, failures and favorite varieties in the comments section below.