Earlier this week I attended a mushroom-growing workshop in Knoxville, led by Bob Hess, owner of Everything Mushrooms. I've thought about growing mushrooms, but it always seemed to require significant investment in science lab equipment. Mushroom spawn plugs looked to be easier, but because of what I'd read I thought it might be difficult as well. When the opportunity to attend a workshop came up I jumped at it.
It turns out to be really quite easy. You need two tools: a drill and a hammer. You'll need plug spawn, of course, and a log. The log seems to be the most important component other than the plug spawn. It must be hardwood, preferably white oak, and freshly cut (which means aged a month or two until the sap stops running); no old logs off the ground. The log should be 4-6 inches in diameter, and 2 feet long or so (or as long as you want bearing in mind you have to be able to move the thing).
Starting on one side at one end, drill holes of the right size (your spawn provider should tell you, but the plug needs to be tight) all the way to the other end of the log, spacing them about 4-5 inches apart. Turn the log a quarter turn and repeat. Then twice more and you'll be done. Push and pound a plug into each hole. If you have some sort of blunt-end punch, countersink the spawn a bit. If you have some cheese wax or paraffin handy and melted, daub some over the holes to close the wounds.
Set the log outside in a shady spot that will get plenty of rain. If possible, avoid direct contact with the soil. Then wait a year. If you don't get any significant rain for a month or you think the log is getting dry, stand the log in a bucket of water overnight.
That's as far as I've gotten, I'll update the progress with a mushroom recipe for Christmas 2011, or sooner if anything happens. If everything goes well, I should be harvesting shiitake mushrooms through at least 2015 from that one log.