Shiitake mushrooms (Lentinula edodes) are a prized crop that has been cultivated in Asia for over a thousand years. Known for their rich, woodsy umami flavor, shiitakes enhance a wide range of dishes—from brothy soups to white pizzas. Recent studies suggest that regular consumption of shiitakes can boost the immune system, and for vegans, they provide a rare natural source of Vitamin D.
If you’re looking to grow your own shiitake mushrooms, cultivating them on logs is a satisfying and rewarding project that’s perfect for gardeners in cooler months. Here’s how to do it.
Best Logs for Growing Shiitakes
The best time to start growing shiitakes is in late fall through winter, when trees are dormant and their wood is filled with nutrients that will support fungal growth. Look for a straight, young oak tree, ideally 4-5 inches in diameter. Oak wood is especially ideal due to its slow decay, which helps the shiitake fungus thrive without interference from other fungi. Other hardwoods, like maple or beech, can also work, but oak remains the top choice for many gardeners.
The length of the log matters, too. Logs around 3 feet long are manageable and have a slower drying rate compared to shorter logs. Avoid longer logs, as they become too heavy when soaked with water. If you don’t have access to your own oak trees, try contacting a local tree service to find fallen logs.
Choosing Shiitake Spawn
To grow shiitakes, you’ll need “spawn”—the starter culture that kicks off the fungal growth. The most common and straightforward option is plug spawn. These are small hardwood dowels infused with shiitake mycelium (the fungal network). A packet of 100 plugs will typically inoculate 5-6 logs, which is ideal for home gardeners.
You can easily find plug spawn from mail-order suppliers. Once you have your spawn, you’re ready to begin inoculating the logs.
Inoculating the Logs
To inoculate the logs, drill holes about 1 ¼ inches deep and 6 inches apart along the length of the log. A standard 3/8-inch drill bit works well for this task. You can mark your drill bit with paint to ensure consistent depth.
After drilling, use a hammer to tap the plug spawn into the holes. This ensures a tight, secure fit. Once the plugs are in place, seal the holes with food-grade wax, like cheese wax, to lock in moisture and prevent contamination from other fungi. You can melt the wax in a can placed in hot water, then apply it to the logs with a cloth dauber attached to a stick.
Caring for Your Shiitake Logs
After inoculating the logs, place them in a shady spot and wait for the mycelium to colonize the wood. This process typically takes 8-14 months. During dry spells, water the logs to maintain moisture and help the mycelium thrive.
Once the mycelium is visible at the ends of the logs, you can start inducing fruiting. Shiitake mushrooms naturally fruit after a heavy rain, but it’s often more reliable to soak the logs for 24 hours in cold water and then give them a gentle tap with a hammer. This stimulates the fungi and encourages the growth of mushroom “pins” (small, rounded mushroom buds), which will grow into mature shiitakes in just a few days.
Harvesting and Enjoying Your Shiitakes
Shiitakes typically fruit best in the spring and fall. Logs will produce mushrooms in cycles (flushes) for three to five years, though the number of mushrooms will decline over time as the fungus consumes the nutrients in the wood. Allow the logs to rest for about three months between flushes for optimal results.
When harvesting, pick the mushrooms promptly to avoid damage from pests like snails and beetles. Use a dry paintbrush to clean off any dirt or debris. Fresh shiitakes can be stored in the fridge for a few days, but they also dry very well if you prefer to store them for longer use.
Shiitakes are incredibly versatile in cooking. Try sautéing them in olive oil and salt, then adding them to soups, risottos, or pasta dishes. To maximize their nutritional benefits, always cook shiitakes for at least 12 minutes.
Final Thoughts
Growing shiitake mushrooms on logs is a fun and rewarding process that lets you enjoy fresh, nutritious mushrooms right from your backyard. With a little patience and care, you can enjoy multiple harvests over several years, and the flavor and health benefits are well worth the effort. Happy growing!