Why Aren’t My Oyster Mushrooms Pinning?

It can be frustrating when you’ve set up your block, but nothing seems to be happening. The
stage where mycelium turns into baby mushrooms is called pinning, and it requires a very
specific set of environmental triggers. The most common reason for a lack of pins is low
humidity. If the surface of the mycelium dries out, it becomes a skin that mushrooms can´t
break through.
The second most common issue is Fresh Air Exchange (FAE). Mushrooms breathe oxygen
and exhale CO2, just like us. If CO2 levels are too high (which happens in stagnant
air), the block will refuse to fruit. You need a gentle breeze or to fan the block a few times a
day to kickstart the process.
Finally, light and temperature play a role. While mushrooms don´t need sun for energy, they
do need a circadian rhythm—a little bit of ambient light to tell them which way is up If your room is too hot (above 24°C for many species), the mycelium might stay in growth
mode instead of fruiting mode. To help optimize your growing environment, we have
hygrometers, humidifiers and humidity tents available on our nordichydro webshop.