OPTIMA Organic Grain Bag – Sterilized with Injection Port

Our OPTIMA organic sterilized grain bag is built for one thing: fast, aggressive colonization.

Formulated by longtime mushroom growers, each 3 lb bag is loaded with our proprietary blend of hydrated, nutrient-rich organic millet and wheat berries. Every bag comes with a self-healing injection port for easy use with spore or liquid culture syringes, plus a 0.2 micron filter patch to keep airborne trash out while still letting your mycelium breathe.

Note: injection port color may vary. It all works the same—don’t overthink it.

Recommended use

Use 1 lb of fully colonized grain spawn for every 5 lbs of bulk substrate.

For these 3 lb injection-port bags, we recommend 2.5–5 ccs of solution per bag.
(More details in the “Inoculation & Colonization” section below on the product page.)

Why add millet?
Short answer: cleaner, faster, more points of attack.

Long answer:

Lower endospore load than rye or wheat = less prone to contamination when prepped right.

Smaller grain size = way more inoculation points in the same volume, so your mycelium can storm through the bag and your bulk substrate like a swarm.

Nutrient-dense = once it takes off, it really takes off, pushing rapid, even mycelial expansion.

Bottom line: millet gives you a denser, more even colonization and a better shot at full, healthy canopies—exactly what Bruise Blue bags are built for.

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