Growing ‘shrooms with a view

Gardeners grow through their gardening experiences. Most of us start out with annuals — the miraculous trip from a little envelope of seeds to plants that sprawl halfway across the yard, bearing flowers or fruit, before they finally succumb to frost. Gradually we begin to see the benefit of perennial flowers, in terms of hours and dollars invested. And if we own property, we begin to grow enduring edibles — berry bushes and fruit trees or French tarragon and rhubarb. Fruit and nut trees and even asparagus beds may outlive the gardener.

Some realizations dawn slowly. It took me decades to fully understand my former neighbor’s observation that trees are just big weeds. He had gardened and managed a 50-acre wood lot for many years before I met him, and he had shed the novice’s idealized view of very big plants. It’s really quite simple: If we are to eat, we need to replace vegetation that doesn’t provide nourishment with something that does.

Trees are usually beautiful, certainly necessary, often valuable — and sometimes old and in the way. Shade is a balm on a hot day, but it can also be a serious problem, particularly for folks whose gardens are nestled in the woods. As the saying has it, nature abhors a vacuum. Trees beside an opening in the woods rapidly grow toward the sunshine. A flourishing oak tree can diminish garden yields far more quickly than an invasion of dandelions or thistles. And when a garden I had laboriously carved from the woods in 1983 began to shrink during the late ’90s, I got it: Trees are just big weeds.

Fortunately, however, weeds do have their uses. Some are edible or medicinal in their own right. All of them can be composted. Trees can be milled for lumber, burned for fuel, chipped for paper or used in log lengths to build garden beds or cabins. And, perhaps best of all, they can be converted into food.

I’m not talking about the sawdust they put in cheap ice cream (yes, for real — leave a dish of “all natural” ice cream on the counter for a couple of hours. If it retains its shape instead of becoming a puddle, it contains wood fiber as a “texturizer”). No, I’m talking ‘shrooms. Shiitake mushrooms, to be precise — those nutty, chewy, expensive gourmet fungi.

Shiitakes grow only in wood, and once you get them started, they’ll produce semiannual crops for up to eight years. The best time to plant shiitake spawn (the actively growing fungus prepared for inoculation) is late winter, but you need to start planning now. You’ll need a good number of logs 3-4 feet long and 3-6 inches in diameter. The wood should be cut after the leaves drop this fall, and it must be taken from a growing, deciduous tree after the sap is down. The best species are varieties of white oak (including chestnut oak, which is common locally), but other hardwoods will yield good crops as well.

You’ll also need to order the mushroom spawn. (See the list of suppliers below.) For large-scale operations, it’s cheaper to order the spawn as a powder. But for ease of handling, it’s worth paying a little more for plugs, which are dowels drilled from logs with shiitake mycelium (the vegetative part of the mushroom). A good starter quantity is 300 plugs, which will require 10 40-inch-long logs or the equivalent. (The length is important only in terms of handling; shorter pieces will produce just as well.)

Your supplier will include instructions and an estimate of the amount of wood required. Suppliers normally ship the spawn in late winter, by which time you should have your logs. If planting is delayed, refrigerate the spawn. (My first time, I didn’t bother to open the box and read the instructions for a few weeks and just left it on a shelf. The spawn had grown into a massive clump by the time I was ready to go, and it was a hassle pulling it all apart, though it still grew just fine.) You’ll also need a drill (see supplier instructions) and beeswax or paraffin.

To inoculate, you cover the whole length of each log with spawn. (In nature, such mushrooms take hold in one spot and gradually spread into the surrounding wood; but because logs rot, any one tree will yield only a meager harvest.) Starting your crop over the whole surface helps ensure that mushroom production begins swiftly and converts all the nutrition in the wood to human food as efficiently as possible.

Drill your holes as deep as the plugs are long, so when you insert them, they’ll be more or less flush with the surface of the bark. If you have a drill gauge, great; if not, you can paint the drill bit or wrap it with a piece of sticky tape as a guide. It doesn’t matter what pattern you use; I tend to think geometrically, so I begin by drilling a line of holes eight inches apart from end to end on each log. Then I drill a second row a couple of inches from the first and staggered halfway from it, then a third row that follows the same measurement as the first row. Continue all the way around the log, with the diameter determining the number of rows. Next, insert a plug in each hole. Then melt wax and seal each plug. This is easiest if the wax is almost liquid, not super hot.

At this point, you’re finished, except for cleanup and piling up the logs somewhere shady. I usually stack them horizontally for the first year but lean them tepee-style after that, to make harvesting easier. You might get a crop by next autumn and will definitely have one the following spring. The yield will gradually increase every six months for a few years and then taper off again. In dry years, it won’t hurt to water the logs now and again while you’re wetting down other things in your garden. If you have an empty barrel or don’t mind bark in the bathtub, you can reliably boost the yield by immersing the logs for 24-48 hours in early spring and early fall.

Shiitake mushrooms are superb fresh, but they aren’t bad dried and reconstituted. Drying is simple: Place them in a brown paper bag in a dry place until they’re leathery, then store them in a tight-lidded jar in a dark cabinet. To use the mushrooms, soak them in hot water till they swell and soften. In my first eight-year cycle, I ate all I cared to, gave them to friends and still ended up with dried mushrooms that lasted another four years.

So shed your guilt about whacking down the tree that’s raining shade on your garden parade, plant some shiitakes, and let ’em grow.

Suppliers of mushroom spawn

* Field and Forest Products Inc., (715) 582-4997, www.fieldforest.net

* Fungi Perfecti, (360) 426-9292, www.fungi.com

* Hardscrabble Enterprises, (304) 358-2921, hardscrabble@mountain.net

* Mushroom People, (800) 386-4496, www.mushroompeople.com

* Northwest Mycological Consultants, (541) 753-8198 www.nwmycol.com