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Recently shaken, colonized grain spawn - Mush Ohio

Blue Oyster Grain Spawn

$19.95
By Mush Ohio
Availability

Fast, forgiving, and made for cool weather.

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.

Blue Oyster (a blue strain of Pleurotus ostreatus) is one of the easiest gourmet mushrooms to grow, and one of the most rewarding. Its steel-blue caps soften toward gray as they mature, and cooler temperatures bring out the deepest blue, which makes it a great fall and winter grow. A mild, savory flavor and tender texture make it a kitchen staple.

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: Blue Oyster (Pleurotus ostreatus, blue strain)
  • 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), or Master's Mix.
  • 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: Cool temperatures around 50–65°F (10–18°C), 85–95% humidity, indirect light (bright enough to read by), and plenty of fresh air. Long stems and small caps are a sign it needs more fresh air or light.
  • 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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