Kit Troubleshooting & Advice

This advice is relevant to all of our Ready-To-Grow kits. If you are concerned about the progress of any of our other kits, please contact us via email or WhatsApp with photos so that we can advise accordingly. Step 1: Don't Panic!

Remember, the time it takes for your mushrooms to sprout can vary based on species, temperature, and season. All reishi species and blood reishi are slow growers and can take up to 3 months to start pinning. In the winter, most mushrooms are particularly slow to grow.

Step 2: Check the Fruiting Hole

Look at the hole in the box. If it shows white or yellowish mycelium for Blue Oyster and Lion's Mane mushrooms, there's a good chance your mushroom is not far away.

White or yellowish mycelium means that your Lion's Mane or Blue Oyster mushrooms are on their way!

For Pink Oyster mushrooms, look for off-white or pink wisps of mycelium. Pink Oyster mycelium tends to be more wispy than Blue Oyster or Lion's Mane so it can be a bit harder to tell by looking at the hole in the box. If you see see some off-white or pink wisps of mycelium your mushrooms are probably on track.

This is a well colonised pink oyster kit. Note that the growing medium looks light with a pink tinge, rather than dark brown.

An example of a dark brown window that indicates lack of colonisation.

Step 3: Adjust the Environment

In nature, fruiting is sparked by a change in season or weather. A change of environment can also help. Try moving your kit somewhere warmer or cooler, with more sunlight or less sunlight, or somewhere with more humidity. This change in environment can help speed along fruiting.

Cold shock (not applicable for pink oyster or blood reishi): If you'd like to speed it along, pop in in the fridge for 1-2 days before resuming your regular care routine. (WARNING: THIS IS NOT APPLICABLE FOR PINK OYSTER/BLOOD REISHI AS THEY CANNOT WITHSTAND COLD TEMPERATURES!)

Step 4: Inspect the Block

If you’ve checked the fruiting hole and you're still unsure, open the box to examine the block inside to see what’s going on with the mycelium. Ensure your block is well colonised like the photos below:

A well colonised Pink Oyster block

A well colonised Lion's Mane block

If your block isn’t looking very colonised, send us photos of each side so that we can assist you.

Step 5: Fruiting Troubleshooting - Dry Opening

If your block seems well colonised but hasn't fruited, it's possible that the mycelium in the area of the slits has dried up slightly and this is inhibiting fruiting. Tape up the original slits with sellotape and make slits in a new area. You can now grow your mushrooms directly from the bag.

Step 6: Check For Competing Organisms

In mushroom cultivation, it's always a race between the mushroom mycelium and other competing organisms. As a result, it's not uncommon to see small patches of competing organisms on your growing medium. They can be green, brown, black, dark yellow etc. If more than 10% of your block is covered in patches of competing organisms, it's likely that you may see some reduction in yield of mushrooms.

If it appears that your block is not well colonised or you see more than 10% competing organisms, please send a photo of each side of your mycelium block to us via email or WhatsApp and we'll help you figure out what's going on or if it cannot be resolved, we send you a free replacement block.

I've tried all of the troubleshooting steps and it's now a couple of weeks past the expected timeframe for pinning that is mentioned in the instructions.

If you've already followed the troubleshooting steps above and it's now past the expected pinning timeframe for your species (as listed in your kit instructions), please contact us email or WhatsApp with photos of each side of the mycelium block that is contained within the box so we can assess its health and recommend next steps.

In mushroom cultivation, competition between mushroom mycelium and other organisms is common, leading to patches of competing organisms on the growing medium. Our kits undergo quality checks in controlled environments before shipment. However, storage conditions and hygiene practices when starting your kit can occasionally result in patches of competing organisms, visible as green, brown, or dark yellow spots.

If more than 10% of your block is covered in patches of competing organisms, it’s likely that you may see some reduction in the yield of mushrooms. Please note: When it comes to reishi, dark red, yellow, and sometimes black patches are normal characteristics on the mature mycelium.

Bear in mind that when it comes to reishi, competing organisms may be more visible because of its much longer growth cycle. This is due to non-sterile air entering the bag when it is inflated. Guidance for dealing with this and ensuring it does not spread is covered in our online reishi kit instructions. If you are ever unsure, please email us with photos so that we can help!

If it appears that your block is not well colonised or you see more than 10% competing organisms (usually patches of green, but anything that is not the colour outlined in the mycelium check step for your specific kit in our online instructions), please send a photo of each side of your mycelium block to us via email or WhatsApp and we'll help!

Unfortunately, fungus gnats are a reality of mushroom growing. They are tiny flies which are attracted to the mycelium you've exposed when you made a slit in or opened the grow bag. They also commonly live in moist houseplant compost. Filling a cup or jar with some apple cider vinegar and a splash of washing-up liquid can help trap them and draw them away from your mycelium. Yellow sticky fly traps can also be an effective way of dealing with the adult flies.

Barriers for prevention

Fungus gnats are more likely to be a problem in the spring and summer and are more likely to be attracted to top fruited species such as King Oyster. For top fruiting species, pre-emptively draping the top of your kit with ultra-fine mesh designed for protecting plants from insects (with 0.5mm or smaller holes) can help keep them from accessing the mycelium. For any mushroom species except for pink oyster or blood reishi:

If you catch the fungus gnats early, you can tape up the opening in the bag and place it in the fridge for up to 5 days. This will slow down their development and kill many of them off. Do not freeze, as this will kill the mycelium. After this, return your kit to your chosen location to continue growing. Treatment with BTI Products such as Mosquito Bits or Mosquito Dunks contain a bacteria called BTI which kills the larvae of fungus gnats but is non-toxic to humans and pets. The solution can be used to mist the block or as a soak (for no more than 1hr) as an early treatment.

When conditions aren’t ideal, mushrooms can start to grow in some strange ways. Don’t worry, if you’re noticing that your mushrooms aren’t looking how they should, you can make some changes to how you’re caring for your kit to get better results.

See our articles below for the most common related issues and how to resolve them. If you have any questions that aren’t answered here, send us an email with some photos and we’ll help you troubleshoot.

• Lion’s mane unusual “coral like” growth

• Lion’s Mane brown/yellow/pink discolouration

Every mushroom is unique

Like humans, how a mushroom looks depends a lot on the environment in which grew and it's unique genetics. Scrolling through instagram you might think that every Lion's Mane or Pink Oyster mushroom looks a certain way, but that's mostly because people usually choose the best photos with the best angles of the most desirable specimens to post. At Fat Fox, we are constantly working to pick the best looking, fastest growing and most delicious strains to cultivate, but it's never an exact science, and we can never control the growing environment in home kits! The fact that your particular mushroom might not meet instagram beauty standards does not make it any less beautiful, special or delicious!

Gourmet mushrooms can not spontaneously become dangerous

As most people are aware, there ARE poisonous species of mushroom. Sadly, this causes a lot of unwarranted fear surrounding mushrooms in general. If you're feeling nervous about eating your unique looking mushroom, just remember that there are plenty of poisonous berries and plants out there, but in the same way that strawberries don’t magically turn into juniper berries or celery into hemlock, gourmet mushrooms can't spontaneously change species! Even if we've accidentally shipped you a blue oyster instead of a pink oyster or a reishi instead of a lion's mane (if this is the case do get in touch and we'll fix it!) we don't cultivate ANY mushrooms at Fat Fox that are not delicious and/or healthy for humans! There’s no need to fear the fungi!

The name blue oyster is a bit of a misnomer. They get their name from their tendency to have a slight blue tinge when they first begin to pin and fruit. As mature mushrooms, however, their colour can range from a light tan, to a brown to grey. Their colour is largely influenced by fruiting conditions. The colder the temperature, the more likely they are to be darker - it is unusual to have dark mushrooms, for example, in the summer or if your house is very warm. Sunlight also can affect the colour of your mushrooms. like humans, mushrooms contain melanin that will darken with exposure to sunlight. We don't however, suggest putting your mushrooms in direct sunlight in an effort to affect their colour as this can dry them out, but a bit of exposure to indirect sunlight can potentially make your mushrooms a bit darker. Mature blue oyster mushrooms will not sadly, ever be actually blue.

Although it might be tempting to pick each new mushroom individually, It’s best to wait until the largest mushrooms are just beginning to flatten out and then harvest the whole bunch together. If you pick individual mushrooms and leave the rest it can affect the flushes that follow and decrease your overall yield.

Mycelium can have a mind of its own. Although your mushrooms should grow only from the hole you’ve created in the plastic, if they've been left a long time before you've started your kit they WILL find a way to escape! Your best bet is to harvest whatever has already started to grow, and then to remove the mycelium block from the box and grow your mushrooms directly from the hole bag instead. See our FAQ on what to do if your box is wet or mouldy.

This blue oyster kit was left in a cupboard for 2 months. It has started to grow through the edges of the box and will begin to consume the box.

While you should never be spraying your Oyster mushroom box so much or keeping so much moisture in your Lion's Mane humidity tent that your box becomes mouldy or sodden, sometimes a box becomes so damaged (especially after several flushes) that it's best to grow your mushrooms straight from the bag.

To do this, simply remove the mycelium block from the box and carry on as normal. Your mushroom should grow from the slits you previously cut.

It’s not uncommon to see some liquid inside of the filter bag. This liquid is metabolites (also nicknamed mushroom pee!) and is simply a byproduct of the mushroom breaking down the substrate or fighting off competing organisms.

In order to deflate bags enough to fit them into the box for shipping, we make a small slit in the side or middle of the microporus filter bag. This is totally normal and should not be a cause for anxiety or concern. If you're growing a top-fruiting mushroom (for example Reishi or King Oyster) please follow the directions on how to prepare the bag to fruit your mushrooms. If you're growing a mushroom that fruits directly from the side of the box (for example Lion's Mane or Oyster) Please read the instructions carefully. Your block should not be removed from the box unless the box is damaged.

A white (or pink in the case of pink oyster mushrooms) dust under your mushroom growing kit means that your mushrooms have started to drop spores. This is not a problem, it just means that you've waited a bit too long to harvest your mushrooms. They'll still be perfectly delicious and the spores put out by a mushroom growing kit are not dangerous. Just wipe down your counter and harvest your mushrooms right away!

It's very important that you keep up with they mycelium growth rate by adding more substrate to your Tea & Coffee Recycle kit as soon as you see fluffy mycelium across the surface. It can be a bit of a tricky balance - add too much substrate and your mycelium might not be able to keep up, add too little and you might get strange looking fruit bodies growing inside your container! If your mushrooms begin to fruit before you have filled your container, harvest all of the fruit bodies with VERY clean hands. Then you can carry on adding substrate regularly to your jar until it is full to the top.

Fruit bodies that develop inside the jar will look strange and spindly. This happens because the the Co2 levels inside the jar are very high and cause deformation of the fruit bodies.

You can use any large plastic or compostable bag as a humidity tent. Just make sure it is large enough to leave some room for airflow around the edges, and for your mushroom to grow.

Usually, our mushroom kits can tolerate a wide range of temperature and humidity, but this can be more challenging during the hot summer months. If you're home environment is very hot and dry and your mushrooms are looking unhappy, there are a couple of easy ways to help: 1) You can choose to remove the cardboard box and fruit directly from the bag that is contained inside. This way, you can place the bag on top of damp tea towel which will help provide a a bit more humidity. 2) If you'd like to keep your kit housed within its box, you can place it on top of an upside down bowl with the damp tea towel or a shallow bowl of water underneath. Bear in mind that mushrooms that are already looking dry and shrivelled will not recover - it is best to harvest these and let the next flush grow in healthy.