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Black Pearl Oyster Mushroom Kit Instructions

Black Pearl Oyster Mushrooms are a genetic hybrid of King Oyster and Pearl Oyster mushrooms. They are a rare and beautiful variety of oyster mushroom that are characterised by their dark brown to black caps and pearl white stems. They have a mild, earthy flavor and a slightly chewy texture.

Each species of mushroom is a different growing experience. Even if you have grown mushrooms before, please read the instructions for your kit carefully before proceeding. If you run into any problems please see our FAQ.

Blue Oyster Mushroom Growing Kit
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Step 1: Mycelium Check

Inside this box mycelium has has been happily breaking down the organic growing medium and converting it into energy. At first the mycelium is often wispy and hard to see, but as it gets ready to produce mushrooms it becomes more dense and white in colour. 


Locate and remove the round cardboard tab on the outside of the box. Check the colour of the growing medium through this 'window'.​​​


Brown =

needs more time in a warm location


Mostly white =

ready to move on to stage  2

If your window is brown, move your kit to a warm location - over 15°C and NO MORE THAN 25°C. Check it once a week until at least 60% of the window is covered with white mycelium.


If your window is filled with over 60% white mycelium you can now move on to step 2.  If you do not want to move on to step 2 at this time, you can keep your kit in the fridge or a cool place for up to two weeks.

Step 2: Finding an Ideal Location

Oyster mushrooms grow best when they are out of direct sunlight and have plenty of humidity and fresh air. Finding or creating the perfect environment is key to getting the most mushrooms out of your kit.

  • Find a humid spot with indirect sunlight to place your box. Near the kitchen sink or in the bathroom is often a good choice.

  • If you've purchased a thermometer/hygrometer, a humidity reading over 50% and a temperature reading between 10°C and 20°C is ideal.​

Step 3: Initiating Fruiting

​In nature the mushroom fruiting process of is triggered by a range of changes in the environment. Fresh air and ambient light become available as the mycelium breaks through the ground layer or the extremities of a log. Seasonal changes bring wetter weather and humidity increases. You will now imitate these changes in the following way:

  • Using a clean knife, puncture the exposed bag in a cross pattern the same size as the hole. This will initiate the fruiting process and your mushrooms will grow from this hole.

  • Mist your kit according to the misting instructions below.

Step 4: Misting

Mushrooms prefer to grow in an environment with 80-90% humidity. Because of this, you'll need to gently mist your kit regularly with a clean spray bottle. You want to create a humid environment for the mushrooms and to keep their bodies moist, rather than to 'water' them as you would a plant.

  • Before your mushrooms begin to grow, a gentle mist 4-6 inches from the hole the 3 times a week will suffice. You do not need to mist the box so much or so close that it becomes sodden.

  • If you are using a large, household spray bottle, be sure it is set to 'mist' instead of 'stream' and mist from 6-8 inches from the box.

  • Once you see your mushrooms begin to pin, mist them twice a day and make sure to keep the mushrooms moist as they won't be able to grow if they begin to dry out. 

Step 5: Pinning

'Pinning' should begin within 1-6 weeks of initiating fruiting. If you haven't seen any pinning after 6 weeks please see out FAQ. Once they have begun to pin, your mushrooms will grow rapidly. Keep the mushrooms moist during this period. 

Step 6: When to Harvest

Harvest your mushrooms before the edges begin to either flip up or to wrinkle, darken and split. A white dust under your mushrooms means they have started to drop spores. Your mushrooms will be at their most tender if you harvest them before they sporate, but they'll still be perfectly delicious if you don't quite catch them in time. Just don't forget to wipe off your counter!

Step 7: Harvest
  • To harvest, twist and pull the entire bunch off at the base. Do not harvest one mushroom at a time, as this will slow your mushrooms' growth.

  • Be sure that you have removed all of the mushrooms' base from the hole. You should be able to see brown growing medium to ensure the next flush.

  • Cut off any cardboard or growing medium that has stuck to your mushrooms. You can store your mushrooms in the fridge for up to a week.

Step 8: Initiating The Next Flush

Did you know that your box has the ability to produce several clusters or 'flushes' of mushrooms over time?


Place your kit in the fridge for 12-24 hours. The change in temperature tricks the mycelium into thinking that the seasons are changing and will encourage them to flush.


You can then return your kit to your chosen location and repeat steps 4-7. Times between flushes can vary from several weeks to several months, so be patient and don't forget to keep the humidity up by misting. Your kit may flush several times, but the amount of mushrooms will reduce with each flush and the time between flushes will increase.

Step 9: What to do with your kit when it stops producing mushrooms

Did you know that fungi play a key role in storing carbon? Trees and plants remove carbon from the atmosphere and fungi break down plant waste to create new carbon-rich soil. Clean air, healthy soil and delicious mushrooms: just one of the many ways fungi are incredible!

Once your box has finished flushing, open the box and remove the mycelium block from its plastic bag. Discard the bag in the general waste. You can now recycle the box and additional packaging and compost the block. Alternately  plant it in the garden to see if it will gain a some energy and produce one last seasonal crop for you! Simply dig a hole in a shady spot, bury the block and cover it over with around 5cm of soil. Water it occasionally to keep the soil moist. 


We hope you've enjoyed growing your Black Pearl Oyster mushrooms!

We're passionate about sharing the diversity of the fungi kingdom & making more  of its edible & medicinal delights easy to grow. Want to try another strain or learn how to cultivate mushrooms? See our full range of mushroom growing kits and cultivation workshops!

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