Mushroom Spawn

Live mushroom spawn can be used to inoculate a many different kinds of mushroom substrates. Mushroom Spawn can be made on a variety of materials. The most popular mushroom substrates to make spawn out of are rye grains, wild bird seed, sawdust, brown rice flour and vermiculite.

For todays example we will be using rye grains fully colonized with Shiitake mushroom mycelium. To get started we will first need to gather up some supplies.

• Fully colonized mushroom spawn.
• A secondary nutritious bulk substrate to add our spawn to.
• Rubbing alcohol for sanitization.
• Scissors to cut open our mushroom substrate bags.
• Medical gloves to keep our skin from contaminating our spawn or substrate.
• An impulse sealer or tape to seal the bag. Clear packing tape works well if no sealer.
• A permanent marker or sticker to write the date and mushroom information on.

Now that we have gathered up all of our materials, it is time to start. First, make sure you are working in a clean environment, preferably not on a carpeted floor. Make sure that no fans or forced air are running. The reason for this is because microscopic spores are constantly around us, naturally, every day. With fans and carpet, you increase the chances of stirring up dust, spores, and other unwanted particles into the air. Lysol can be helpful to reduce the number of bacteria and spores in the air. Working in front of a laminar flow hood is the best option, but a still air box works as well.

The use of medical gloves and a face mask is highly recommended during the entire process.

Sanitize the outsides of both the mushroom spawn bag and the mushroom substrate bag with rubbing alcohol. It is easiest to wet a paper towel with rubbing alcohol and wipe the bags with it. When you are wiping the bags down, make sure to get into the gusseted areas of the bags. Don’t miss the corners either if you want to be thorough.

Now that your bags are clean, we need to break up the colonized rye grains inside of the mushroom spawn bag. Do not open the bag to do this. Instead, mix the contents of the spawn bag by gently kneading it with your hands. The goal of this step is to separate all of the rye grains that have become entangled with mycelium during the colonization process.

Each grain will act as an inoculation point once it is mixed with your mushroom substrate. Mycelium will branch out in thread-like growth patterns from the colonized rye grains. Generally, the more inoculation points you mix into your mushroom substrate, the faster and more robust the colonization of the bulk substrate will be.

Once you have mixed the mushroom spawn bag, take your scissors and cut off the tops of both the mushroom spawn bag and the mushroom substrate bag, both directly below the seal. It is a good idea to cut open the mushroom grow bags in this manner in case you want to reseal the bag later.

Now that both of your bags are open, dump the mushroom spawn into the mushroom substrate bag. Once you have added the desired amount of mushroom spawn, you will need to reseal the top of the bag you just added the spawn to. It is preferred to seal the bag with an impulse sealer, but other methods will work. One such method is to simply use clear packing tape to seal the top of the bag. It is a good idea to leave some air inside the bag before sealing it to make mixing easier.

With the mushroom substrate bag sealed, mix the contents together by gently kneading and/or shaking the bag. The way you mix the bag is not detrimental as long as the bag is not punctured or ripped open during the process.

With the mushroom substrate bag completely sealed and the contents mixed, you have completed your transfer of live mushroom spawn to a bulk substrate.