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Recently shaken, colonized grain spawn - Mush Ohio

Pearl Oyster Grain Spawn

$19.95
By Mush Ohio
Availability

The classic oyster, and the ideal first grow.

Two ways to order:

  • Made fresh to order (ships in 2–3 weeks): We inoculate your bag after you order, so it arrives fully colonized and at peak vigor instead of aging on a shelf.
  • Ready to ship (ships in 1–3 days): When we have a fresh batch on hand, you can skip the wait. If it shows sold out, choose made fresh to order.

Pearl Oyster (Pleurotus ostreatus) is the most forgiving gourmet mushroom you can grow. It colonizes quickly, tolerates a wide range of substrates and temperatures, and rewards you with generous clusters of soft, velvety caps. Its mild, slightly sweet flavor works in nearly any dish.

Includes WeMush tracking: Every order ships with a QR code linked to WeMush, our cultivation tracking platform. Scan it to view specimen details, log observations, and follow your grow, free with any Mush Ohio purchase.

Specifications

  • Species: Pearl Oyster (Pleurotus ostreatus)
  • Product: Fully colonized grain spawn
  • Weight: Approximately 1600 g (about 3.5 lb) wet weight
  • Packaging: Filter patch spawn bag
  • Skill level: Beginner-friendly

Cultivation guidelines

  • Substrates: Pasteurized straw, hardwood fuel pellets (HWFP), Master's Mix, or other lignocellulosic materials.
  • Spawn rate: About 5–10% of the substrate's wet weight. Many home growers go up to about 15% for faster, more contamination-resistant colonization.
  • Colonization: 70–75°F (21–24°C) in the dark, typically 1–3 weeks.
  • Fruiting: A wide window of roughly 55–75°F (13–24°C), with low 60s ideal; 85–95% humidity; indirect light (bright enough to read by); and plenty of fresh air.
  • Harvest: As caps go from domed to nearly flat, while the edges still curl slightly down, before they turn up or wavy.

These are general guidelines; optimal conditions vary with your setup. Oysters release a lot of spores, so harvest on time and avoid fruiting them in a bedroom.

Storage and handling

  • Inspect the bag on arrival for damage or contamination.
  • If not using right away, refrigerate at 35–40°F (2–4°C).
  • For best results, use within 1–4 weeks of receipt.

Bundle and save: Buy four bags of grain spawn and get the fifth free with code BUY4G1FREE. Mix and match any spawn in our Grain Spawn collection.

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