I've been growing shiitake mushrooms for several year now and I don't know why more people don't do the same. They are fun and easy to grow, absolutely delicious, easy to store for future use, and good for you, too.
First some taxonomy
A nice crop of Shiitake mushrooms on water oak logs.
Mushrooms are the fruiting structures of a fungus. Most of a mushroom fungus consists of mycelia living and eating invisibly inside dead logs, roots or stumps. Periodically, the fungus sends up a mushroom that will release spores to sail on the wind and find more dead plant material and start a new generation of fungi. Molds and yeasts are also fungi, and they produce little fruiting structures too. Fungi are not plants; they are not animals, either. Scientist recognize five kingdoms of life: Monera (bacteria and blue-green algae), Protista (protozoans and certain unicellular algae), Fungi, Animalia and Plantae. Fungus cells have a nucleus that contains genetic material, unlike bacteria and blue-green algae, which do not have nuclei. Fungi are multicellular, unlike the unicellular protists. Fungi do not have an embryo stage as do animals. Fungi cannot produce their own food by photosynthesis as do plants.
Some history: The shiitake mushroom (Lentinula edodes) is probably native to China. Shiitakes have been used medicinally there for at least 6000 years. They are considered a symbol of longevity. Shiitakes have been cultivated for more than 1000 years. It is a major agricultural crop in Japan, where about half of world production occurs. Shiitake cultivation is new to the United States, having begun only a few decades ago.
These shiitakes are ready for harvesting.
Consumption of shiitake mushrooms is said to have antiviral, antifungal, antibiotic, and anti-tumor effects. Consumption of shiitake mushrooms significantly lowered blood cholesterol levels and lowered high blood pressure in laboratory animals. Shiitake mushrooms contain all eight essential amino acids in better proportions than do soy beans, meat, milk, or eggs. They are high in leucine and lysine, two amino acids that are scarce in grains. Shiitakes are a significant source of vitamins A, B, B12, C, D and Niacin. They even have quite a bit of protein: 13-18% of dry weight. Shiitakes contain lentinan, which has been shown to be important to the body's immune system. Lentinan derived from shiitake mushrooms is used to treat cancer patients in Japan. Shiitakes contain high concentrations of several potent anti-oxidants.
How to grow:
To grow your own shiitake mushrooms you will need some fresh cut hardwood logs about 3-4 ft (90-120 cm) long, and 3-5 in (7-12 cm) in diameter. Any kind of oak, hickory, maple, etc. is fine. You drill holes in the logs and then insert little wooden dowels that have been impregnated with shiitake spawn into the holes. You stack the inoculated logs and keep them moist and shaded, and in six months or so you get a crop of mushrooms on each log. Thereafter, you get another crop every few weeks for two years or more. Complete instructions and the mushroom spawn are available from any of several mail order supply mushroom farms. You can start out with as little as one log, but the typical "starter" kit has enough spawn for 8-10 logs. That will produce enough mushrooms for a couple years for a family of four, and costs less than $25.
Sumptuous shiitakes in the kitchen.
How to harvest:
Shiitakes are ready to harvest when they are big enough to handle: from about an inch (2.5 cm) across up to 3 in (7.5 cm). No need to wait until they get larger, because they only get spongy and more watery. My understanding is that the number of cells in the mushroom does not increase as it enlarges; they just hold more water. Small 'shrooms are less watery and have a more concentrated flavor. I like them best at about 2 in (5 cm) across. I often pull a shiitake mushroom right off the log and eat it raw.
How to enjoy:
Gently brush the dirt off the 'shrooms; don't wash them in water because they tend to soak it up. Cut off the tough stems. Saute the caps in olive oil. Add to soups. Slice raw in salads. Use in marinara sauces. The flavor and texture of shiitakes turn spaghetti and pizza into special gourmet meals.
I used to dry the mushrooms for storage, but now I just put them in a freezer bag and freeze them for future use. I freeze the stems in a different bag and when I get a mess, I puree them in the food processor and make an absolutely delicious, thick, rich soup.