Sterilized Grain for Mushroom Spawn (3lbs)

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Experience extremely fast and dense colonization! Perfect for colonizing and mixing with substrate in a monotub for maximum yields.
  • RAPID COLONIZATION BLEND: A proprietary mix of Millet and Wood Dust that guarantees a high-yield colonization that is superior to traditional grain substrates, such as Rye Berries. Millet's size maximizes the surface area in which mycelium can grow, and the wood dust ensures the moisture content is perfectly distributed. Mycologists consider this blend as the fastest colonizing mix on the market!
  • PERFECT FOR MEDICINAL AND GOURMET MUSHROOMS: Whether you are growing lions mane, oyster, medicinal mushrooms, or many other species of mushrooms, this substrate will provide the nutrients your mycelium will love!
  • SUPERIOR STERILIZATION PROCESS: Our proprietary sterilization process is best-in-class and includes hospital-grade sterility testing.
  • EASY TO USE: Perfect for inoculation via spore injection, grain-to-grain, or by adding agar directly to the bag. Works great for at-home hobbyists and large-scale cultivators.
  • SELF-HEALING INJECTION PORT: Safely inject your liquid culture or spore syringe directly into the bag via a self-healing injection port.

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Our special blend of millet and hardwood oak dust maximizes mycelial growth.


Step-by-step instructions and video guides included.


Self-healing injection port and micron filter patch to keep contaminants out.


Hospital grade sterility-testing and batch-tracking.


Mix 3 lbs of Grain with Lightning Colonization Tek™ with 5-10 lbs of Substrate for Dung-Loving Mushrooms in a monotub.


Where can I find spores or liquid culture?

Although our products don't come with spores or liquid culture, you can easily find them online from several suppliers. We recommend sourcing them from Use checkout code MUSHROOMSUPPLIES for 5% off.

What kind of mushrooms can I grow?

Unlike our Grow Kit In-A-Bag™ and Substrate, you can use this grain bag for virtually any variety of mushrooms, including:

  • dung-loving mushrooms
  • wood-loving mushrooms such as lion's mane and oyster
How much substrate should I mix with this grain?

We recommend mixing 3 lbs of colonized with 5-10 lbs of substrate.

How long can I keep the bag before using it?

Because our grain is fully sterilized, it can last several months if stored correctly. We recommend keeping it in a box and placing it in a closet or cabinet. Make sure the grain avoids extreme temperatures, liquids, and direct sunlight.

Can I grow mushrooms directly in the grain bag or do I need a grow bin?

We recommend mixing this grain (once colonized) with substrate in a grow bin.

Although not recommended, if you wish to grow directly inside your grain or substrate bag, we suggest mixing 1 lb of colonized grain inside the substrate bag.

If your preferred method is to grow directly inside a bag, your best option is simply to get the all-in-one Grow Kit In-A-Bag™.

Where can I find step-by-step instructions?

You can find step-by-step videos, instructions ,and FAQs in the Guides section of the website. If you still can't find the answer to your question, email us at!

Is my bag too wet or too dry?

We take special care to ensure each bag is perfectly hydrated and sterilized.

Please note that moisture and hardwood oak dust can settle toward the bottom of the bag during transit. Because of this, we recommend shaking your grain bag before inoculating it. This will help with mycelial growth by evenly distributing moisture.