Why and when should I soak it?
Note: half the weight of the shiitake-farm is water. So if a 5kg Shitake farm is weighing in at 2.5kg… then you got a desert in there: and as you know, mushrooms don’t grow in the desert! So if it is getting close to 3kg it needs a dunk. Tap water is fine.
Soaking the farm (plus cooling it) simulates an autumn rainstorm. As far as the little shiitake-farm is concerned, it’s dreaming of being in a puddle on the forest floor. Together with raising the temperature a couple of days later, simulates a warm sunny autumn day. The shiitake sense this and knows that the forest is now a perfect humid environment to grow.
You may need to soak the ‘farm’ to initiate initial pinning. After this, soak it only when it becomes dry.
Another tip is to leave it outside for a few days and give it a good soaking/spray with the garden hose. Set the hose nozzle to a fairly firm stream and try to replicate a powerful winter rainstorm.
Oh no! I think I’ve dried it out?
Shiitake are very hardy, and it’s likely that it’s okay. Soak it in water to rehydrate. It may bounce back quickly or may be dormant for a while.