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Recently shaken, colonized grain spawn - Mush Ohio
Black Pearl King culture growing on a Mush Ohio agar plate, labeled for WeMush tracking

Black Pearl King Grain Spawn

$19.95
By Mush Ohio
Availability

Premium Black Pearl King grain spawn for gourmet harvests.

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.

Black Pearl King is a hybrid of Pearl Oyster (Pleurotus ostreatus) and King Oyster (Pleurotus eryngii). It pairs the King Oyster's dense, meaty texture with the Pearl Oyster's fast colonization and forgiving nature: rich umami flavor, generous yields, and striking dark-capped clusters. A favorite of home growers and small farms alike.

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

  • Strain: Black Pearl King (P. ostreatus × P. eryngii hybrid)
  • Product: Fully colonized grain spawn
  • Weight: Approximately 1600 g (about 3.5 lb) wet weight
  • Packaging: 6 mil polypropylene filter patch bag for gas exchange and contamination control
  • Produced: In our sterile lab, using locally sourced grain

Why growers choose our spawn

  • Selected genetics: Chosen for vigorous mycelium, prolific fruiting, well-formed caps, and deep flavor.
  • Fast, confident colonization: Establishes quickly in bulk substrate, so competitors have less room to take hold.
  • Sterile protocols: Produced under strict lab procedures to give you a clean start.
  • Adaptable: Performs on hardwood sawdust, straw, or Master's Mix, and suits a range of setups.

In the kitchen

Savory umami flavor, dense meaty stems, and tender caps. Excellent grilled, seared, roasted, or added to soups and stews.

Cultivation guidelines

  • Substrates: Hardwood fuel pellets (HWFP), straw, Master's Mix (soybean hulls and hardwood sawdust), or other lignocellulosic materials.
  • Spawn rate: Mix thoroughly into pasteurized or sterilized bulk substrate at 5–15% spawn to substrate by wet weight.
  • Colonization: 70–75°F (21–24°C) in the dark, typically 1–3 weeks depending on substrate.
  • Pinning: Drop to 60–68°F (15–20°C), raise humidity to 85–95%, add indirect light, and increase fresh air exchange significantly.
  • Harvest: Usually 1–2 weeks after pinning, when caps begin to flatten and before the edges curl upward.

These are general guidelines; optimal conditions vary with your setup.

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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