Research linking vitamin D to an increasingly long list of health benefits is pouring out of universities and flooding medical journals, some associating adequate vitamin D levels to a lower risk of developing certain cancers, a higher chance of surviving cancer, and increased protection against diabetes, infections, heart disease, and perhaps even dementia. Our body can manufacture the substance when the sun strikes our skin in ideal conditions, but most Americans are dreadfully deficient in this superstar substance. That's because much of the country doesn't get enough year-round sunshine. And because we wear so much sunscreen to protect against skin cancer—a sensible precaution, but one that blocks natural vitamin D production.
THE DETAILS: It's hard to get what experts say is a reasonable vitamin D target, 1,000 to 2,000 International Units (IU) a day, from food. But one potent source of vitamin D is often overlooked: the shiitake mushroom. These mushrooms have long been used medicinally in Asia (some studies have found the fungi to hold antitumor properties). But many shiitake mushrooms you'll find at the supermarket are grown in sawdust, not on logs, as nature intended, so they don't have as many nutrients as they should. And while log-grown shiitakes go for up to $40 a pound in Japan, you can enjoy their superior flavor and increase your nutrient intake by growing your own at home.
Rusty Orner, owner of Quiet Creek Herb Farm and School of Country Living with his wife, Claire, shared his mushroom expertise at the Pennsylvania Association for Sustainable Agriculture's 19th Annual Farming for the Future conference. While most participants in the room were farmers, serious gardeners, and/or sustainable-food advocates, the truth is, growing shiitake mushrooms in your yard isn't very difficult.
Here's what you need to know about growing shiitake mushrooms at home.
• Find your logs. If you have trees on your property, you can use logs or branches from freshly cut, living hardwood trees (white, red, or pin oak; sugar maple; or ironwood). Ornel says it's best to cut between October and April because that's when the moisture content is ideal. The logs should be three to eight inches in diameter. You can also find suitable logs from timber stand improvement cuts. Cut the wood into three- to five-foot sections. These will be the logs your mushrooms will grow from for the next five to nine years, if you do things right.
Read on to find out how to select your spawn.