Transferring Spawn Bag to Bulk Substrate

Spawning Grain to Bulk Substrate Bag

Once your grain bag has fully colonized, follow these steps to transfer the spawn to the substrate. 

Note: It is important to maintain a sterile environment during the entire process to avoid contamination. Be sure to follow proper hygiene and sterilization procedures at all times. 

• Wear gloves to ensure your hands are clean of any potential contamination
• Spray and wipe your workplace with 70% isopropyl alcohol
• Wipe your grain bag with 70% isopropyl alcohol and paper towel but make sure not to get any alcohol on the filter patch because alcohol will kill mycelium

Step 1: Take your mushroom spawn bag and shake it gently to distribute the spores evenly throughout the bag.

Step 2: Open the bag of mushroom spawn and pour it into the substrate bag. Be careful not to touch the inside of the bag with your hands or any other objects as this can cause contamination. Be sure to evenly distribute the spawn throughout the substrate.

Step 3: Once the spawn has been added to the substrate, carefully seal the substrate bag using a heat sealer. If you do not have a heat sealer, thinly fold over the top of the bag three times over and paper clip it shut. Air should not be able to enter or exit through the fold. 

Step 4: Place the substrate bag in a warm and dark location with a temperature between 65-75°C. Allow it to incubate for several weeks until the mycelium has completely colonized the substrate.

Note: The ideal temperature for a spawn run depends on the type and strain of mushroom.

Step 5: Once colonization is complete, sanitize your scissors with alcohol wipe then cut across the top of the bag. Gently alternate between compressing and expanding the center of the bag to introduce fresh air into it. Repeat this motion for approximately 30 seconds. Secure the upper part of the bag by neatly folding it over and fastening it with a paper clip. Return the bag to a clean setting and patiently await another 7-10 days.