Mushroom Grow Kit Guide

Congratulations on your new mushroom grow kit

All of the grow kits are bags of living mushroom mycelium (mushroom roots) that are ready to start growing immediately. If you are not ready to start the kit upon receiving it or plan to give it as a gift - you can postpone fruiting/growing by storing it refrigerator temperature for up to 7-10 days.

All you need to start growing this kit is a small spray bottle and a plastic tote and lid. The basics to growing any of our mushroom grow kits is to provide it with humidity and fresh air. Most varieties grow best between 60-75 degrees F, with certain varieties being able to grow at slightly lower or higher temperatures which we’ll talk about more below.

The first step to starting your kit is to make a slice in the bag for the mushrooms to grow out of. The variety of mushroom you are growing will determine what opening you will make. Please see below.


Slice a large “H” or an “X” on the broad side of the bag, then fold over the top, leaving the open side exposed. Your opening should be an 8x8 inch square, with flaps that lay flat to keep the surface of the block and mycelium moist - creating an inviting environment for mushrooms to start growing!

Chestnut Mushrooms

Cut off the top of the bag off entirely leaving a  3-5 inch flute of bag above the top of the substrate block (like the picture to the left)! These walls will help trap moisture creating a good environment for the mushrooms to start growing.

Lion's Mane

With a razor knife cut TWO 1in. by 1in. X's on the broad side of BOTH sides of the bag. Roll down the top of the bag squeezing out all of the air and tape down to hold the fold. Just like the picture on the right.    

The Lion’s Mane will start to grow where it senses oxygen, so taping down the top will help direct its growth to the holes you have created. Keeping the holes near the top of the block will give your mushrooms room to grow out and hang down the side of your bag.


Shiitake mushrooms produce a better yield if they receive a COLD shock prior to cutting open the bag. Store your kit in the refrigerator, basement, or depending on the weather outdoors for 24 hours. It just needs to be about 10-20 degrees cooler than average indoor air temperatures.    

Shiitake also benefit from a PHYSICAL shock as well, hold your kit about 2 feet off the ground and drop it, letting it smack to the floor. Then make a 10 inch slit across the front of the bag, just underneath the filter. This exposes the block to the fresh air, but not too much! Shiitakes need to be very humid when they first start to form so keeping the bag on helps to keep in the humidity initially.

Place back into your humidity chamber (we'll discuss more about his below) and in about a week, once you see a number of small round dime sized formations pushing up against the bag - remove the bag entirely and place back into the humidity chamber.

Storing Your Kit

Mushrooms need both humidity and fresh air to stimulate their growth. You can achieve these conditions at home by simply creating a humidity chamber using a plastic storage tote and a misting bottle. Once you make the correct cut for your kit, place the kit into your humidity chamber and leave the lid slightly askew . Oysters lay down with the opening facing up, Lions Mane-Chestnut-Shiitake stand straight up.

Every day, at least once a day, VIGOROUSLY FAN out the tote using lid and LIBERALLY MIST the inside walls of the tote. Scroll down for more detail about storage requirements and when to harvest.


Pick a spot

Mushrooms do not require sunlight to grow and thrive best in 60-75 degrees Fahrenheit with 80% humidity. Choose a place in your home or yard out of direct sunlight. The basement, garage, bathroom, office, or laundry room... We’ve had customers tell us that they put in the bathtub!

Pick the best location that will be conducive to maintaining your humidity level. To ensure that your kit is receiving enough humidity you want to make sure you can always see some condensation on the walls of your humidity chamber. 


***Once mushrooms reach a certain maturity level they will start to release spores. This is part of their natural reproduction process. Some people are more sensitive to spores or may have an allergic reaction to them which usually presents as respiratory irritation/coughing. This is rare but good to keep in mind. For this reason you may consider growing your kit in a well ventilated area, a protected place outside, in the garage, basement, not a main living area or bedroom. Harvesting the mushrooms while they are young will also help reduce the amount of spores that are released.


DAILY Tender Love & Care

Everyday, at least once a day, VIGOROUSLY FAN your the tote using the lid and LIBERALLY MIST the inside walls of the tote with your spray bottle. Fanning is CRUCIAL for your mushrooms to form correctly. Mushrooms breath in Oxygen and release Carbon Dioxide, which will pool up in the tote if you do not fan it out. Recommend at least 1 minute of vigorous fanning before misting!

Baby mushrooms should start to form on the top of the block within about 1-2 weeks. It is crucial to keep your grow kit humid at the very beginning, if the surface of the block gets too dry it is unlikely that the mushrooms will start to pin. Be diligent with your misting!


Higher Co2 usually results in longer stems and smaller caps because the mushrooms are growing upwards, like they would through the soil, searching for fresh oxygen and the right environment to fruit, mature, and release their spores.
Co2 can pool at the bottom of the container and sometimes fanning by hand just isn’t enough. It’s a good idea to take the kit completely out of the container periodically and wave the container around or blow a fan directly into the tote for just a few minutes once a day. You can also set the container outside with the lid off for a few hours on overcast days, mornings, evenings, or shaded areas to really ensure proper ventilation.

Time to Harvest

After the mushrooms start to form they should be ready to harvest in another 5-7 days. Most mushrooms are ready to harvest once their caps open up slightly although there are nuances to each variety explained below.

After harvesting the best way to store your mushrooms is in a brown paper bag in the refrigerator for up to a week, sometimes longer!



Once the cap/outer edge of the mushrooms have flattened out and are less turned under. Put your hands at the base of the cluster and gently rock back and forth until it breaks free. Careful! Sometimes they like to jump off of the block.


These are ready to harvest once the cap has opened up and becomes more hemispherical but before they become flattened or concave. Also if you look at the underside of the mushroom, once the mushroom veil starts to break away from the stem. Grab the base of the cluster and gently rock it off of the block

Lion's Mane

Once the hairs reach about a ¼ - ½ inch in length. Put your hand underneath the mushroom and on top and lightly twist to harvest.


Once the cap opens up and there is no longer a rim underneath. Use a scissors to cut the mushroom off of the block .

More Mushrooms

After your first harvest the block can produce a second, third, sometimes fourth flush but usually much smaller than the first. Keep the block in your humidity chamber and continue to mist daily to keep the humidity up. You should see a second flush within a few weeks.

If you do not start to see the second pinset form in 1-2 weeks you can try letting your block rest for a week by halting the misting and fanning. After its week of rest, run your block under cool water for several minutes and then place it back in your humidity chamber and give it a second go.

Let us know if you have any questions along the way. And please share your pictures by sending them to us directly or tagging us on social media! Find us on Facebook a nd Instagram @mycophiles_garden. We love to see your success and would be happy to offer any advice if things don’t seem to be going quite right. You can reach us at [email protected]. Best of luck!