Shiitake blocks incubate far longer than oyster bags. The folder gives 60 to 80 days at 22 to 26 C, 500 to 1000 lux and 65 to 70 percent humidity, on a cycle of 4 hours light and 20 hours dark. The manual's table stretches this to 50 to 120 days at 20 to 30 C.
The block passes through visible stages. A thick mycelial coat forms at 6 to 8 weeks. Bumps, which are clumps of mycelium, appear at 9 to 10 weeks. Then the surface browns and the coat hardens. The bag is removed once the block is a third to half browned, with core moisture near 80 percent.