Grey Oyster Mushroom Grow Kit

What Makes Grey Oyster Special:
Grey Oyster (Pleurotus ostreatus) is the classic oyster mushroom variety—the one you'd find growing wild on hardwood trees in nature. It thrives in temperatures between 50-80°F, making it one of the most adaptable varieties for year-round indoor growing. With a firm texture and delicate, sweet flavor, it's prized by chefs for its versatility in everything from stir-fries to risottos.

Why RMS Tree Oyster Blocks Are Different:
Our Grey Oyster blocks arrive fully colonized on a hardwood-based substrate blend, allowing growers to skip substrate preparation and incubation. Each block is inspected before shipment and includes access to variety-specific setup, care, troubleshooting, and harvest guidance.

Flavor Profile:
Mild, savory, and slightly sweet with a beautiful anise-like aroma when fresh. The texture is meatier and heartier than other oyster varieties, making it excellent for dishes where you want substantial mushroom presence that holds up to high-heat cooking.

Instructions

Getting Started:

1. Remove block from shipping box and inspect for white mycelium coverage (this is normal and good!)
2. Find the pre-cut opening or cut a 4-6 inch X-shape on one side of the bag
3. Place in indirect light with good air circulation
4. Keep at room temperature (60-75°F is ideal, but tolerates 50-80°F)

Daily Care:

1. Mist the cut opening 2-3 times daily—we recommend mornings and evenings
2. Aim for the air around the opening, not directly at forming mushrooms
3. Keep substrate moist but not waterlogged (if you see pooling water, reduce misting)
4. Ensure good air circulation (crack a window or use a small fan on low)
5. Within 7-10 days, you'll see white "pins" forming—this means success!

Harvesting for Best Results:
Harvest when caps begin to flatten and edges start to curl upward. Tree Oysters are best when picked young—as they age, the flesh becomes tougher. Twist and pull entire clusters from the base, or cut with a clean knife. Don't leave stems behind as they can invite contamination.

Getting Multiple Flushes:
After first harvest, rest the block for 7-10 days without misting. Then submerge the entire block in clean water for 12-24 hours (we use a cooler or large bowl). Drain completely and resume regular misting. Second and third flushes typically appear within 1-2 weeks and can be just as productive as the first.

Pro Tip from Our Team:
If your block seems to stall, try the "shock method"—place it in the refrigerator overnight, then return to normal growing conditions. This temperature change often triggers pinning.