Pleurotus ostreatus

“Pleuro” means formed laterally or in a sideways position(stem and cap relationship). “Ostreatus” refers to the “oyster” shape and color. Oyster mushrooms are generally a commercially grown mushroom. In the wild they grow on hardwood logs. Commercially, they grow on a medium of chopped wheat straw or wood sawdust that has been formed into large blocks wrapped in a thin plastic. This medium is pasteurized to eliminate harmful pathogens and then inoculated with the mushroom spawn.

It takes 10-14 days for the mushroom spawn to permeate the growing medium creating thread-like hairs called mycelium. This requires a constant temperature range of 78-84° F, high humidity (90-100%) and a high content of CO2. At this point, the mycelium is ready for pinning.

“Pinning” is the term used to describe shocking the mycelium into forming clumps called pins. These pins are the actual fruiting bodies of the mycelium. To shock the mycelium it is necessarily to dramatically reduce the amount of CO2 in the growing environment. Pinning takes 7-14 days.

To help the tiny mushrooms grow light is introduced to stimulate fruit development, as oyster mushrooms are “phototropic” (grows towards light). Mist watering applications while the mushrooms are young help prevent the mushroom caps from cracking, an undesirable trait in marketing the mushrooms.

Each mushroom “block” can be harvested three times before the mycelium fruit is depleted, with a new flush of mushrooms approximately every 10 days for 5-7 weeks.