How To Use Our Mushroom Grow Bags

  • Inject bags, through the foam injector port, with 2-5 mL of spore solution or up to 5 mL liquid culture.
    • Use 70% alcohol to sterilize the injection site and the needle between injections. Use of flame to sterilize the needle is not recommended, it risks damaging the injector port.
  • Place inoculated bags in a warm location, 70-80f.
  • Watch for mycelial growth, it will be white in color.
    • Colors such as black, blue, green, and red are all signs of contamination, discard the bag. Make sure your spores or cultures are not contaminated. Do your inoculations in a clean environment with sterile handling procedures.
  • After the bag is 20-30% colonized, break up the colonized part and mix it throughout the bag. Take care to not puncture the bag or break the bottom seal. This step will speed up colonization by a few weeks.
    • It can help to get some air in the bag before mixing.  Hang the bags on clothes hangers using spring clamps. This pulls air through the .2 micron filter patch keeping the bag sterile.
  • When the bag is completely colonized, it’s time to expose the mycelium to fresh air. This starts the fruiting process. Cut the top 2 inches of the bag off, fan with fresh air 5-6 times a day. Mist inside of the bag with water but don’t allow water to pool. Keep the bag closed between fresh air exchanges to maintain high humidity.
    • An alternate method is to cut the bag off about 3 inches above the block. Place the blocks in a clear rubbermaid type container with a lid and fan with fresh air as above. You can mist water on the walls to help raise the humidity.
    • The colonized blocks can also be broken up and used to fill tubs.  You can cover them in a casing mix and fruit in a more traditional method.

More information about mycology can be found on sites like




The most critical decision is your source of spores. There are a lot of poor quality vendors currently, and almost all instances of contamination or lack of growth can be traced back to the spores. Our bags are hydrated and sterile, we guarantee it. Spore syringes are not sterile, they must contain only the spores we want.

We are not responsible for contamination once the bags are injected.


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Yes, bags can be left in a lighted room. Keep them out of direct sunlight.

Mushroom Spawn Store

Once the bags are injected, can they be left in a lighted room until white appears, or should they be kept in the dark?
Thank you.

Buckshot Charlie

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