Find an area with indirect sunlight and gentle, indirect airflow. Avoid placing your block near direct heat sources or air conditioning vents.
Place the grow block in the green tray with the folded side down. Do not remove the block from the bag.
Take a sharp, clean knife and cut a 1½-inch X right in the center of the bag. You want the blade to just barely cut into the block — about ¼ inch deep.
Gently lift the flaps created by the X and spray underneath — 1 to 2 sprays on each side. Mist the inside of the humidity dome so that it's completely covered in condensation. Place the dome over the green tray and block. Make sure all 4 vent holes on top are completely open.
Mist the inside of the humidity dome 2 to 3 times daily. You want to keep a layer of condensation on the inside of the dome at all times.
Your mushrooms should begin pinning (the first signs of growth) within 7 to 14 days. Once your mushrooms begin to grow, remove the humidity dome for the rest of the grow. If your home is especially dry, ease the transition by removing the dome during the day and leaving it on at night for 1 to 2 days.
Once the dome is off, mist your growing mushrooms directly 2 to 3 times daily.
Your Blue Oysters are ready to harvest once the cap edges start to flatten and uncurl. Gently twist the entire cluster from the base to remove it from the block.
Store your fresh Blue Oysters in a paper bag in the refrigerator for up to 7 days. Always wash and cook your mushrooms before eating.
You can often grow a second (and even a third) harvest by flipping the block over and restarting the process from the opposite side. Cut a new X, mist, dome, and repeat.
Don't panic — some blocks take a little longer depending on temperature and humidity. Make sure you're misting 2 to 3 times daily and that the vent holes on the dome are open. Blue Oysters fruit best in cooler temperatures (55–70°F). If your home is warmer than that, try moving the kit to a cooler spot. If nothing happens after 3 weeks, reach out to us at info@midammushrooms.com and we'll help you troubleshoot.
This is a sign that your mushrooms need more fresh air. Long, leggy stems with small caps mean CO₂ is building up around the block. Make sure the dome is off once pinning starts, and try placing the kit somewhere with gentle airflow — not a closed closet or sealed cabinet.
You're probably not misting enough, or the air in your home is very dry. Increase your misting to 3 to 4 times daily. If the block surface has dried out significantly, you can give it a heavier misting to rehydrate the top layer. Avoid soaking or submerging the block.
Green or black patches usually mean contamination has taken hold. This can happen if the block was damaged, exposed to dirty conditions, or if humidity was too low and the mycelium weakened. A small spot of green can sometimes be managed by carefully cutting it away, but if it's spreading, it's best to compost the block and start fresh. Contact us at info@midammushrooms.com if this happens — we'll make it right.
This is totally normal — mushrooms will fruit wherever they find a gap or thin spot in the bag. You can let them grow and harvest as usual, or gently peel back the bag to give them more room. It doesn't mean anything went wrong.
Watch the cap edges. Blue Oysters are ready when the edges of the caps start to flatten out and uncurl — they'll go from curled tightly downward to flattening or even turning slightly upward. Don't wait until the caps are completely flat or wavy, as the mushrooms will start to dry out and lose flavor. When in doubt, harvest a little early rather than a little late.
Place them in a paper bag (not plastic — they need to breathe) and keep them in the refrigerator. They'll stay fresh for 5 to 7 days. Avoid washing them until you're ready to cook.
Yes to both. For freezing, cook your mushrooms first (sautéed is best), then freeze in a sealed container. Raw mushrooms don't freeze well. For dehydrating, slice them thin and use a food dehydrator or a low oven (around 150°F) until they're completely dry and crispy. Store dried mushrooms in an airtight container — they'll keep for months and rehydrate well in soups, stews, and stir-fries.
Loved your Blue Oysters? We grow kits for a bunch of different varieties — Pink Oyster, Lion's Mane, Chestnut, and more. Each one grows a little differently and tastes completely unique.
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