As an extra service to our customers, you can sign up for an e-mail service, in which we offer advice for your homegrown mushroom process. You can sign up by clicking the button below. If you sign up the day you start your Grow Kit, you will receive e-mails corresponding to how far along you are in the process.
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FAQ for your Growkit
Below we answer the most common questions regarding Grow Kits
How should I store the bag of mycelium, before I start my Grow Kit?
The bag of mycelium can keep for up to three months in the refrigerator, in case you don't want to start your mushroom project right away. The ideal temperature is between 2 and 5 degrees centigrade. We advise not to freeze your mycelium.
How do I get started?
Before getting started, it is a good idea to kill off all potential bacteria in the bucket.
This is easily done with a clean washcloth and a bit of household spirits or by giving it a pour with boiling water.
To get your Grow Kit running you need, beside the bucket and the mycelium, coffee grounds. The grounds should be as fresh as possible - cooled!
Mix the grounds from one, two or three pots of coffee with the mycelium inside the bucket, using a clean spoon. Then close the lid and wait 2-3 days until the mixture has been completely covered with white mycelium.
How fresh do the coffee grounds need to be?
We advice against using grounds that are older than 3 days, as you otherwise risk contamination through green mold or anaerobic bacteria.
If the grounds are stored for more than 3-4 hours before mixing it with mycelium in the Grow Kit, we recommend that you store it in the refrigerator until then.
Do I mix the content every time I add fresh coffee grounds?
No, you only mix the mycelium and the grounds the first time you put it into the bucket. From then on, when you add coffee grounds, you simply put it onto the white mycelium in the bucket, in a thin and even layer, using a clean spoon.
How often should I add coffee grounds?
When the last added coffee grounds are covered in white, soft mycelium, you can add fresh grounds. The white layer typically takes 2-4 days to spread. Avoid squishing the grounds into the bucket, and do not add more than an even layer of approx. 1-2 cm grounds at a time.
Can I add the coffee filter?
Yes, you can definitely add the coffee filter into the mix. The mushrooms love the wood fibres in the filter.
How much coffee grounds does the Grow Kit require in total?
You should simply keep adding grounds to the Grow Kit until it is filled to the brim.
Can I use something other than coffee grounds?
If you make sure to sterilize/pasteurize it first, you can use almost any kind of plantfibre as growth medium, such as sawdust, straw, cardboard, wood chips or the like.
One advantage of using coffee grounds though, is that it is pasteurized when you make the coffee, and as such it can be used with no other processing needed.
How long before the mushrooms come out?
This depends on temperature and humidity, and of course on how much coffee you drink. Usually it takes between 6 and 8 weeks before you can harvest your first mushrooms. After this first harvest, you can expect a new one approx. every two weeks. The Grow Kit will produce fewer and fewer mushrooms for every harvest, and therefor we recommend restarting the Kit as described in the instructions on the bucket.
How many mushrooms can I produce with a Grow Kit?
This also depends on what conditions the Kit is exposed to. Normally it will produce mushrooms three times, giving a total of 1/2 kilo mushrooms. After each harvest you should add a bit of water to the Grow Kit. The substrate in the bucket might also shrink a bit after a harvest. In this case, you can add a bit of extra, fresh coffee grounds. Then you can restart the Kit by adding new coffee grounds, as described in the instructions on the bucket.
I'm going away on vacation. What do I do?
If you are going away, or for some other reason you can't take care of your Grow Kit for a longer period of time, you can put your Grow Kit in the refrigerator. At low temperatures the mycelium goes into hibernation, and you can simply pick it up where you left off once you are home and ready to continue.
If the Kit is filled and overgrown, a trip to the fridge could actually help the growth in the bucket. The mushroom will believe that winter is coming, and when introduced to warmer temperatures again, after a few days in the refrigerator, it will hurry to produce as it believes it might be its last chance before the frost sets.
In any case, you can always use this trick when the bucket is full and ready to produce mushrooms.
What are the optimum growth conditions?
Described below are the optimum growth conditions. Be aware, you can still achieve fine results without following the instructions 100 %.
The mushrooms development can be divided into two fases:
The Growth fase is when you add coffee grounds and when the mycelium gets to spread. Here the mushroom grows strong enough for the next fase, where it gives fruit. The optimum conditions for your Grow Kit in this fase are room temperature (20-25 degrees) and no light.
Next fase is when you have filled your bucket to the brim, and the last coffee grounds have been covered with white mycelium. Now the Kit is ready to give fruit. In this fase, the optimum conditions are 15-20 degrees, high humidity and light surroundings (no direct sunlight). If you can not create these conditions at home, you can place the Kit in the refrigerator for around 24 hours. This cheats the mushroom to believe winter is coming, and it will hurry to bear fruit. To achieve high humidity in dry surroundings, you can spray the mushrooms with water from time to time.
When do I remove the tape?
When the Grow Kit grows the mushroom after approx. 10-14 days into the Fruiting fase, it will push the tape aside itself. If it doesn't fall off, you can help it along by pulling it off. Do not remove the tape from the holes from which the mushrooms do not grow.
When should I harvest?
When the Grow Kit has grown a cluster of mushrooms, and the mushrooms heads are horisontal, you should harvest.
When can I restart my Grow Kit?
After you have harvested a third time, your Grow Kit will probably stop producing mushrooms. Now you can remove approx. 80 % of the substrate from the bucket, using a clean spoon. You can use the remaining 20 % to restart the Kit with fresh coffee grounds. The substrate you have removed from the bucket you can compost, or you can leave it in a moist part of your garden or balcony, and perhaps it will produce mushrooms. The holes in the Kit can be re-covered with new tape, which you can buy at a local pharmacy. Alternatively, you can stop by our shop on Jægersborggade 35 in Copenhagen we'll give you a piece of tape for free.
If the substrate is contaminated by mould or if it is too dry to restart, you can buy fresh mycelium in our shop at 60 DKK/bag to start again, once you have cleaned your Grow Kit bucket.
What do I do if the mushrooms are very small and dry?
This could indicate that the environment is too dry. Try moving your Kit away from heatsources or draft. You can also try spraying water on the mushrooms.
What do I do if colorful things start showing up in my Grow Kit?
Anything in your Grow Kit that is not coffee grounds should be white or beige. A yellow or red'ish fluid might appear, which is normal. If you on the other hand observe green mould (rarely also orange) it is a clear sign of contamination.
Contamination can occur if the Kit has not been properly cleaned before using it, for example, if you've used dirty tools to add the coffee grounds, if the substrate is too dry, or if mould spores in the air for some reason concur the white oyster mushroom spores.
If you only see a small patch of green mold in your Grow Kit, you can - in most cases - simply remove the attacked area with a clean spoon. Keep a daily eye on the development, and remove the mould if it returns. Make sure the substrate is moist at all times.
If the contamination has spread to a larger area of the Kit, you will have to discard all of the substrate. Then, clean the bucket thoroughly and wipe it with household spirits. You can then restart the Kit by buying a new bag of mycelium in our shop.
Also, if the substrate is contaminated with mould or is too dry, you can buy a fresh bag of mycelium in our shop at 60 DKK/bag, and restart the proces - after you have cleaned your bucket.
What if mushrooms grow inside the bucket?
If the bucket hasn't yet been filled, and it bears fruit inside the bucket, you might have waited too long before adding fresh coffee grounds. Remove all the sprouted mushrooms from the bucket, and add fresh coffee grounds.