Black Reishi Skull Kit Instructions

Reishi is a slow-growing mushroom, producing one crop per year. With this kit, you will watch the mycelium slowly develop and produce otherworldly waxed red brackets.

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

Step 1: Mycelium Check

Inside the jar, mycelium has has been happily breaking down the organic growing medium and converting it into energy. The jar is equipped with a lid that has a hole covered by micropore tape, allowing for the air exchange necessary for the mycelium to thrive Before getting started with your kit, take a look at the colour of the mycelium to see whether it is ready to move on to fruiting conditions.

The jar on the far left needs more time. The jar in the middle is more colonised. The skull on the right hand side is full of thick, white mycelium and is ready to move on to step 2.

If your mycelium needs more time to develop, keep the lid closed and place it in a warm, dark location - over 15°C and NO MORE THAN 25°C. Check it once a week until it is almost completely covered with dense white mycelium.

Please note that red and /or yellow patches are normal characteristics for mature Reishi mycelium.

If you are not ready to move on to step 2 but your jar is, you can store it in the fridge for up to a month.

Step 2: Check For Pins

Once your jar in completely colonised with white mycelium, bring it out into the light. Wait until the top of your black reishi skull has started to form pins before moving on to the next step. Pins are the very start of the mushrooms starting to form and in reishi, they will look like new lumps and bumps on the surface. Take off the lid of your jar once a week to check how it's looking.

Pins have started forming on the surface (highlighted in red). This jar is slightly more advanced than necessary for moving to step 3, as the pins have already begun climbing toward the top.

Step 3: Initiating Fruiting

Once your black reishi skull begins to pin, it's now ready to move on to fruiting conditions. Take your fruiting bag and pour 1-2cm of water into the bottom. Next, take the lid off your jar and carefully place it inside of the bag. WITHOUT BREATHING INTO THE BAG, inflate the bag to create space for your mushrooms to grow and roll and clip the top edge closed. You do not need to create a tight seal, as the reishi will need a bit of air to grow. One fold and one clip in the middle will suffice. Your black reishi will grow from the opening at the top of the skull.

If using the clear display box:

Start your reishi with the steps above. Once the reishi antlers have reached around 3-4cm long, transfer it to your display box. Generously mist your reishi and the walls of the box with clean water once a day to maintain a high level of humidity.

Reishi skull kept within the bag with 1-2cm of water at the bottom. The top of the bag is rolled down and clipped closed.

Step 4: Finding an Ideal Location

Reishi grows best when it is warm, out of direct sunlight and located somewhere where it will remain undisturbed. It is a slow-growing mushroom, producing one crop per year.

Your reishi jar will grow inside the fruiting bag provided which will keep the humidity level high whilst creating a CO2-rich environment that will cause the reishi to form an antlers.

Choose a spot in your home with indirect sunlight (direct sunlight will dry out and burn your reishi) where your reishi can stay undisturbed for a long time. Ideally, the temperature should be between 21-27°C. Keep in mind that as your reishi grows taller, it will naturally lean toward the light. If you want to guide its growth, observe it regularly and adjust its position as needed.

Step 5: Growing

Over the next few months, your mushrooms will grow slowly from the top of the growing medium inside the jar. It can take 1-3 months for the young caps to emerge. Initially, they may appear as lumps and bumps on the top. They will form an 'antler' shape as they grow and seek oxygen. Be careful not to disturb them.

If growing in the bag:

Once the reishi has climbed to around 5-10cm tall you can cut the top of the bag close to the level of the jar to expose them to the fresh air, which may help them form brackets, or you can leave them inside the bag to maintain the antler formation.

If you decide to cut open the top of the bag, brackets will start forming at the ends of the 'antlers.' With the bag now open, it's important to maintain humidity by keeping the water level at the bottom topped up and misting your reishi with clean water regularly. Aim to have about 1-2 cm of water in the bag at all times. At this stage, it's important to move your reishi to a location where the spores won't be easily inhaled, such as away from your bedside table. Breathing in large amounts of spores can be harmful to your health, so it's best to place it in a well-ventilated area.

If using the display box:

You can keep your reishi skull inside of the display box whilst it grows. If you'd like it to develop brackets at the end of the antlers, you can increase airflow by opening the door for around 15mins once or twice a day, which will have a similar effect. If doing this, be sure to mist your reishi and the sides of the box with clean water 1-2 times a day to keep up humidity.

As the brackets or antlers grow, their rims or the tips of the antlers will be white, which means that it is still actively growing. Once the rims or growing tips have turned from white to orange and finally to red, the mushrooms have finished growing.

Green spots on the surface of your reishi?

Because reishi takes so long to grow, the presence of competing organisms is not uncommon. As your mushrooms grow, you will likely notice small patches of competing organisms (usually green) on the surface of the mycelium. This is because non-sterile air entered the bag when it was inflated. We recommend using a cotton bud dipped in alcohol gel hand sanitiser to carefully clean the mould off the affected area.

With the bag you can cut it down to the level of the jar to provide more oxygen to the reishi if you want it to form bracket structures at the end of the antlers.

If the reishi skull is being grown in the display box, it must be misted once a day to keep humidity up.

Step 6: What to do once it’s finished growing

You can now choose to harvest your reishi or keep it as for display.

If keeping for display:

Remove your reishi skull from the plastic bag. Since it has finished growing, it no longer needs the extra humidity provided by the bag and water. The reishi and the mycelium in the skull jar will naturally dry over time and you can keep it as a decorative object.

To harvest your reishi:

Carefully remove the fruiting bodies from the growing medium by twisting them off. You may need to use a spoon or a sharp knife.

Fresh reishi are very tough, which means eating them directly is impractical. You can chop up fresh reishi mushroom and boil in water for 20-30 minutes to make a tea to extract its medicinal compounds or prepare your own tincture.

TIP: It's best to wait until ALL of the tips of your reishi brackets or stag horns have turned completely (and quite dark) red before you harvest rather than attempting to harvest a bit at a time. It can be hard to wait, but you want to give your reishi the chance to grow to its full size before harvest.

Step 7: How to Prepare your Mushrooms

Fresh reishi are very tough, which means eating them directly is impractical. You can chop up fresh Reishi mushroom and boil in water for 20-30 minutes to make a tea or prepare your own tincture.

Step 8: What to do with your kit when it's finished 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!

If you've harvested your reishi and would like to discard the remaining mycelium and substrate, you can simply cut it out of the jar and add it to your compost heap. You can also try burying it in your garden and it's possible you may get a surprise flush in the future.

We hope you've enjoyed growing your Reishi 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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