Fruiting Oyster Mushrooms
Updated: Dec 10, 2019
In this guide we will cover off how to fruit oyster mushrooms! Oyster mushrooms are a staple for the hobby mushroom grower. Easy to cultivate and forgiving of any mistakes. They quickly grow, and you can have a fresh harvest of oysters on your plate in just a couple weeks! There are many different types of oysters, but here we will focus on the phoenix oyster. Phoenix produces huge mushrooms which are edible and tasty nonetheless.
Once the Oyster block is fully colonised it will be ready to fruit!
We want to separate fruiting oyster mushrooms into three steps. The first is opening the block, the second is primordia formation, or 'pinning'. The third is fruiting.
Step 1 - Opening
Assuming we have a fully colonised bag, we just want to cut open a small square or slit in the bag to the open air. Phoenix, as like most oysters, are a prolific fruitier, and opening the entire block to the atmosphere will cause far too many pins and a waste of energy. So we want to direct the mushrooms where to grow. This is done but cutting a golf or tennis ball sized hole in the side or the top of the bag. With the air exchanges and the humidity over this opening, primordia should start forming there.
Step 2 - Primordia Formation
To form primordia, or 'pins' you need to provide the block and the opening with four elements.
Light, humidity, fresh air exchange, and the correct temperature.
Light - Contrary to popular belief, mushrooms actually need a bit of light around the blue spectrum. They like blue light because it scatters and gets to shady damp spots easier. The same reason the sky looks blue to humans is because it scatters blue light. You can use a cool blue fluorescent light, or just good old fashioned natural light! But do not leave it directly in the sun. It should have around 12 hours of light a day. Mushrooms won't grow in your dark closet!
Humidity - During primordia formation, the oyster blocks like it damp, (wetter than other types of mushrooms). Oysters like to pin at as close to 100% humidity as possible. If you are using a small fruiting chamber and do not have a pond fogger and/or humidifier, you need to ensure you lightly mist or spray the block with water 4-5 times per day.
Fresh Air Exchange (FAE) - Mushrooms love to create CO2, they are masters at it. If there is too much CO2, they just won't fruit. To prevent this we need to ensure there is plenty of fresh air exchange around the oyster block.
Ideally the air needs to be circulated and replaced 5-8 times per hour. This can be achieved by using a 'shotgun fruiting chamber', or using fans to circulate fresh air into the growing chamber.
Temperature - Oysters like a mild temperature, and pink oysters prefer a more tropical temperature.
Between 16-20 is great for phoenix oysters, and slightly warmer for pinks.
You will find pink oysters do not like to grow fast below 14 degrees.
Step 3 - Fruiting
This is the part we have been waiting for.
All going well, you've provided your block with the perfect conditions and got some good pins growing. Now is the time to take them through adolescence into maturity. At this time the humidity can be dropped slightly back, but still needs to be high. Over 85% is good. The temperature should remain between about 16-20 degrees. Try to keep the humidity and temperatures constant during this stage and the oyster should form.
If you let phoenix grow they will become huge. I like to pick them before they get too large, when they are just perfect size to fry them with some eggs and toast!
Once picked, place the mushrooms in a 1 degree environment (i.e the fridge) as quickly as possible.
If stored correctly, your oysters can last up to 10 days!
Step 4 - Dunk and Repeat
After this you can re-hydrate your blocks and see if you can get a second flush! Be careful not to water log the block. Try to get some moisture back into it and see if it will produce some more mushrooms! You'll be surprised just how much mushrooms will grow from a single block. If the block still appears damp flip it over and cut a hole on the other side!
Fruiting oyster mushroom is a fun and exciting way to grow your own mushrooms. They fruit really fast and within a week or two you can have fresh oyster mushrooms on the dinner plate!