How to Grow Shiitakes in Jars

Substrate Preparation

• 1

  Place 3 1/2 cups of vermiculite into a bowl. Slowly add water to the vermiculite while stirring. Add only enough water to uniformly moisten the vermiculite. Tilt the bowl. There should be a small amount of liquid visible. If too much water is added, place the vermiculite in a sieve to drain. Once drained, it will have the perfect water level.

• 2

  Add all the brown flour at once. Mix together until the brown rice flour evenly coats the vermiculite. Fill the jars with the mixture to within 1/2 inch from the top. Do not compress or tamp down the substrate. It is very important for the substrate to remain loose and airy to allow the mycelium to colonize the substrate easily. Remove any substrate from the upper edges to prevent easy contamination.

• 3

  Top off the jars with dry vermiculite. This helps prevent airborne contaminants from reaching the substrate after inoculation. Cover the jar with a 5-inch-wide strip of aluminum foil folded in half. Ensure the edges are crimped tightly to the jar. Cover the top of the jar loosely with another piece of foil measuring 5 inches by 5 inches.

Sterilization

• 4

  Pour approximately 1 inch of water into a pressure cooker. Stack jars in the pressure cooker. If you have a rack that fits within your pressure cooker, insert it first, then stack the jars.

• 5

  Place the pressure cooker over medium heat for 15 minutes. When steam starts escaping the rocker or vent, turn the heat down until only a small steady stream of steam escapes. Remove the pressure cooker from heat after 45 minutes and allow it cool overnight.

• 6

  Wash your hands with antibacterial soap. Sterilize your hands and work area with isopropyl alcohol. Remove the jars from the pressure cooker.

Inoculation

• 7

  Shake the spore syringe to mix any spores stuck to the sides back into the syringe mixture. Loosen the top layer of foil. Place the tip of the syringe in the flame from a lighter until it is glowing red. Remove the tip from the flame and allow it to cool for a few seconds.

• 8

  Remove the loosened upper layer of foil. Pierce the foil attached to the jar near the edge and push the needle in approximately 1 inch. Dispense a small amount of spore mixture. Repeat the process at three other holes. You should use no more than 1 1/2 mL of spore mixture per jar. Reattach the upper layer of foil.

• 9

  Repeat inoculation Steps 1 and 2 for each jar. Place the jars in a warm dark space. The temperature should be no higher than 81 degrees Fahrenheit and no lower than 70 degrees Fahrenheit. After five days there should be white specks within the substrate. This is the growing mycelium. If you see anything that is not white growing in a jar, contamination is present. Throw the jar away . It will take 14 to 28 days for the mycelium to completely fill the jars. At this point they may be removed and exposed to light to start the fruiting process.