You can grow a mini-mushroom forest indoors, says Elizabeth Millard, author of Indoor Kitchen Gardening. For success, choose varieties that need the kind of growing conditions you can provide in your home. "Oysters and wine caps are easy for beginners to grow. As you get more experience, you can try Shiitakes and Lion's Mane mushrooms." Shiitake mushrooms are shown here.
Millard says growing mushrooms indoors is more about fun than a big difference in the taste of store-bought mushrooms. "It's also about availability. I can't find lion's mane or wine caps to buy, but I can grow them at home."
Indoor Kitchen Gardening, by Elizabeth Millard
How many mushrooms can you expect to harvest? Millard, who explains the growing process in Indoor Kitchen Gardening, says you may get "quite a lot. My oyster mushrooms kept growing, and I got maybe 10 cups. It's kind of like cut and come again harvesting. Smaller mushrooms will also come up after you've picked the first ones."
Millard likes wine caps, portobellos, and shiitakes (shown here). Mushrooms don't need to grow in complete darkness, she says. "I know a teacher who grew them in sawdust in a terrarium. Think about how mushrooms grow in the wild. They just get the light that filters in through the forest. The more you can replicate what happens outside, the better the plants will do. You don’t want to block them from all light. They're not like some sea creatures at the bottom of the sea. But they don't need a blast of full sunlight like tomatoes, either."
Inoculated Log with Shiitake Mushrooms
A kit with an inoculated log and good instructions makes it easy to grow mushrooms indoors. You can also start mushrooms from purchased spores, which are almost invisible, but that's tricky for beginners, says Millard. Spores are somewhat like seeds, she adds, while spawn are comparable to transplants. "Spawn gives you a jump-start. It takes longer to grow mushrooms from spores." Kits can be purchased online, but some sellers don't ship year-round. A supplier Millard uses, Field & Forest, ships kits only from November to May, although it ships some kinds of spawn year-round.
Indoor Mushroom Kit
Not all mushroom growing kits contain logs. To grow the mushrooms in this kit, simply cut open the box and follow the directions for providing moisture. The mushrooms will start to grow in a week or two.
While you can grow mushrooms in sawdust or other media, Millard likes wheat straw because it allows good air circulation and holds moisture well. For easy handling, first chop the straw into small pieces. Then - unless you're using pasteurized straw - boil the straw for about 45 minutes, at a temperature of 160 to 170 degrees F., to help avoid problems with disease.
When your straw has "cooked" and cooled down, drain the water, but don't discard it. Save it to use it later; it will give your mushrooms a nutritional kick. Let the straw come to room temperature before adding the spawn.
Coffee Grounds for Mushrooms
Millard gives her mushrooms a sprinkle of used coffee grounds for extra nutrition without extra cost. If you're not a coffee drinker, ask for used grounds at your local coffee shop; you may be able to get them free.
Mushroom spawn often looks like a block of old cheese, Millard says. Crumble it into small bits and add it to your medium, like the straw shown here.
Mushroom Spawn in a Bag
Although you can grow mushroom spawn in almost any kind of container, an ordinary plastic bag is cheap and easy to use. Just poke plenty of holes in the bag for ventilation.
Mushroom Spawn in Containers
Instead of a bag, you can put the spawned straw in a pan or other container, and top it off with some potting soil. Millard says she heard of a gardener who used a plastic laundry basket with holes in the sides. "The mushrooms grew through the holes."
Your mushrooms are ready to harvest when the caps and stems separate easily. Unwashed mushrooms stored in a paper bag in the refrigerator will keep for a few days.