Sterilized Mushroom Grain Spawn Bag

Growing mushrooms at home starts with clean grain. Our sterilized whole oat grain spawn bags are prepared and ready to inoculate. No soaking, no cooking, no pressure cooker required. Just inject your liquid culture and let the mycelium do the work.

Each bag is filled with properly hydrated whole oat grain, sterilized and sealed in a Unicorn mushroom grow bag with a 3T filter patch and a self-healing injection port. The filter patch allows gas exchange while blocking airborne contaminants, and the injection port lets you inoculate cleanly without ever opening the bag.

What’s included:

• 2 lb sterilized whole oat grain (prepared weight)
• Unicorn grow bag with 3T filter patch
• Self-healing injection port

How to use it:

Shake the grain to break up any clumps, then inject 3-5 ml of liquid culture through the injection port using a clean syringe. Give it a gentle shake to distribute the culture, then store in a warm, dark spot around 70-75°F (21-24°C). You should see mycelium beginning to colonize within 5-10 days. Once the grain is fully colonized, usually 2-4 weeks, it’s ready to be broken up and mixed into your bulk substrate.

Whole oats are a go-to grain choice in cultivation because they have a good surface-area-to-nutrition ratio, hold moisture well without going waterlogged, and colonize reliably across a wide range of species.

Compatible with:

This grain spawn works well with any liquid culture or spore syringe. It’s commonly used with Psilocybe cubensis strains, and a variety of gourmet species including oyster, lion’s mane, and shiitake.

Storage:

If you’re not inoculating right away, store the bag in a cool, dry place out of direct sunlight. Properly stored bags remain viable for several weeks. For longer storage, refrigeration is fine, just let the bag come to room temperature before inoculating.