Oyster mushrooms are one of the easiest mushrooms to grow at home. You can buy a kit and are pretty much guaranteed success (for anyone who loves growing things I recommend you give it a try – a couple of options are here – Mushroom gourmet or Parkvale). To get them growing on a larger more reliable scale it’s a bit more involved but it’s the same basic process.
First sterilise the substrate the mushrooms will be grown on to prevent moulds growing. I use straw and ‘boil’ it in a 44 gallon drum. It’s then drained and left to cool.
Adding mushroom spawn is the next step. Spawn can be likened to the seeds of plants. Because it’s so tiny it’s cultivated on grains to bulk it out and make it easier to work with. I receive this spawn infested grain and mix it up with my sterilised straw in bags.
The bags are moved to a dedicated growing room. The humidity, temperature, air flow and light need to be carefully controlled to meet the exact growing requirements mushrooms need. Very very high humidity (nearly dripping point) is the main requirement. I don’t use any chemical control on the mushrooms so I have to make sure things are kept very clean to reduce the occurrence of bugs.
The temperature dictates how quickly things work. In a few weeks the mushroom spawn overtakes the bag of straw.
Now is the critical time to hang the bags. Previously I pack them together to let them naturally heat each other but now they need to be hung so the mushrooms have room to grow. They push out through cuts I’ve made in the bag and quickly turn into full grown mushrooms.
And they won’t last long. The mushrooms are picked over a few days and are kept cool. Once purchased, keep them in a paper bag in the fridge and consume them within a week or so.