Grow Guides
How to Grow Pearl Oyster Mushrooms
● Velvety and dense with a light seafood flavor
● Colonize on grain spawn
● Fruiting conditions 50 to 70 deg F on hardwood substrate and high humidity
● Liquid culture to harvest 4 to 12 weeks
Materials and Space Needed –
– Clean (sanitized) area with indirect sunlight, temperatures ranging from 50 to 70 degrees F, and a relative humidity of 90% to 95%
Optional, but potentially helpful for grow environment: small ultrasonic humidifier, countertop humidity dome/tent, combination thermometer-hygrometer, cooling fan or heating mat as needed
– Gloves, isopropyl alcohol, distilled water and spray bottle, scissors, strong adhesive tape or heat sealer
– Good Mushroom Pearl Oyster liquid culture syringe
– Good Mushroom Starter Grain Bag
– Good Mushroom Substrate Grow Bag
– Optional materials include hair net, face mask, countertop tent/Martha tent, monotube for bulk grow
Step 1 – Sanitize all materials using isopropyl alcohol including your work space, liquid culture syringe and needle, and the entirety of the starter grain bag
Step 2 – Shake the liquid culture syringe thoroughly to mix the mycelium. Attach the needle to the syringe and insert into the self-healing port. Inject 2 to 3ml of liquid culture in 3 to 4 different locations in the grain by repositioning the needle.
Step 3 – Re-sterilize the self healing port with isopropyl alcohol and place the starter grain bag in a dark room-temp location and let it sit undisturbed. Your starter grain will being to colonize over the next 7 to 10 days.
Step 4 – After 30% to 40% of the grain has been colonized (turned white), gently redistribute the grain and mycelium by massaging the outside bag to help increase the rate of growth and coverage. Let it sit until it is 100% colonized.
Step 5 – Thoroughly sanitize your gloved hands, the work space, 100% colonized grain bag, substrate grow bag, and scissors, by spraying with isopropyl alcohol.
Step 6 – Break up the grain and mycelium (massage bag) until all of the grain is loose.
Step 7 – Open the very top of the substrate grow bag by cutting it with sanitized scissors above the micron filter, and empty the contents of the starter grain into the top of the substrate grow bag.
Step 8 – Seal the top of the substrate grow bag above the micron filter with strong adhesive tape (packing tape) or heat sealer.
Step 9 – Distribute the starter grain thoroughly by shaking and massaging the sealed substrate grow bag until the colonized grain has been thoroughly mixed with the substrate. This will help with fast and equal colonization of the mycelium.
Step 10 – Place the bag in the same colonization location (dark and at a temperature of 70 to 75 degrees F) and do not disturb for 5 to 7 days. You will not unseal the bag again until the substrate is fully colonized and ready for fruiting conditions.
Step 11 – After 5 to 7 days (or 30% to 40% white), gently massage and redistribute the mycelium through out the substrate grow bag and place back in the same location until it is fully colonized.
Step 12 – Once fully colonized (completely white), sanitize your gloved hands, the entire outside of the substrate grow bag, and scissors. Lay the bag on its side, upright, or hang in your fruiting location (ex: counter top tent), and with the knife cut an “X” in the bag. The ideal location for this cut is the center of the bag that is facing up if its laid on its side, or facing out if it is hung or upright. Be careful to not cut too deep and damage the mycelium. This will introduce FAE (fresh air exchange) and space for the fruit to grow while helping to keep the mycelium and new mushrooms moist.
*Note – your fruiting location will be your controlled location including a sanitized surface, indirect sunlight 8 to 12 hours per day, and a relative humidity of 90% to 95%
Step 13 – Harvesting your mushrooms will take place when the cap of the mushroom is almost fully open and flat. Cap edges will begin to get wavy and release spores beyond this point. The quality of your mushrooms is much better if harvested before this happens. Simply twist and pull the full mushroom from the substrate, clip any remaining dirt from the bottom of the stem, and store in a breathable container in the refrigerator before enjoying your hardwork and patience!














