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Organic Sterilized Grain Bag with Injection Port














Certifications | USDA certified organic |
Moisture content | Hydrated to a target of 50% |
Bag weight | 3 lbs |
Our best-selling organic sterilized grain spawn bag was formulated by mycologists to maximize the speed and size of your mushroom grow. (All that's required is a spore syringe or liquid culture!)
Each spawn bag contains our proprietary grain blend featuring hydrated, nutrient-rich, organic millet and wheat berries. Bags also include a self-healing injection port for use with a spore or culture syringe plus a 0.2 micron filter patch to block airborne contaminants while providing even gas exchange. Note: Color of injection port may vary.
Spawn to bulk ratio
We recommended 1 lb of colonized grain spawn for every 5 lbs of manure or hardwood sterile substrate. We also recommend using 2.5-5ccs per 3 lb injection port bag. (See Inoculation and Colonization below for full details.)
Why millet?
Millet has a much lower endospore load than rye and wheat, making it less prone to contamination. And its small size means your spawn will have many more inoculation points for the same volume of grain. By using millet, the mycelium will spread more evenly and abundantly through the substrate. And, as a high-nutrient medium, it also encourages rapid mycelial expansion.
Sterilization
North Spore grain spawn bags are sterilized in a commercial-grade autoclave. Sterility is verified using biological indicators and temperature sensors.
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To inoculate the grain bag, simply inject your spore or culture syringe through the port in a sterile location. We always recommend clean hands and latex or nitrile gloves to reduce the introduction of contaminants.
It is best practice to wait a minimum of 1 week after arrival before injecting grain bags to ensure they were not compromised during transit. Rest assured that your purchase is 100% guaranteed. If your bag was compromised, we will replace it.
We recommend using 2.5-5ccs per 3lb injection port bag. We do not typically recommend using an entire syringe in one bag. Doing so adds excessive moisture which can create over saturation in the bag. This over-saturation can pool and is prone to being anaerobic and the mycelium will have a hard time colonizing.
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Allow your bag to colonize in a cool location out of direct sunlight. Temperature for incubation shouldn't exceed 75 degrees F or dip below 55 degrees F. After a couple weeks, you should start to see mycelium growing on the grain.
You'll notice the white mycelium growing outward from the injection point. When it has grown three to four inches you should, without opening the bag, carefully break up the colonized grain and mix it into the uncolonized grain. This will dramatically speed up the colonization process.
When the bag is completely white with mycelium your spawn is ready to use. This may take a couple weeks to a month or more depending on the species and vigor of your culture.
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Grain bags should be stored at room temperature out of direct sunlight. No refrigeration is necessary. They can also be stored for several months before use.
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North Spore's products shall only be used for lawful purposes. North Spore does not condone hallucinogenic mushroom growing in jurisdictions where it is illegal.
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Always tops.

Finest in the northeast⭐️✨
Great customer service that is second to none in my opinion.Clean products at a reasonable price! Thank you North Spore
North Spore
We really appreciate your support, Autumn! Thanks for the great review.

will use this product again
This product is just as described and pictured. it works for any level of mushroom enthusiast. I will definitely use this product again
North Spore
Thanks, Michelle! We really appreciate the kind review.

So far so good.
I inoculated two bags a few weeks ago and everything looks great. Clean and easy so far.
North Spore
Thanks for sharing, Michael! We really appreciate your support.

Easy peasy for the diy type
North Spore
Thanks, Billy! We really appreciate the review.

Top quality products
I’m fairly new to the mycology hobby at a few months in but I can tell immediately these are quality products. My biggest worry starting out was contamination and I’ve yet to see it yet using North Spore products. I’ve tried a few options already and guarantee North Spore will be my go to for grains and substrates for a long time.
North Spore
Thanks for the great review, Nick! Our team is here if you need anything!

Organic grain bag
Bag was good clean no damage when it came worked as it should recommend
North Spore
Thanks for sharing, Andrew! We really appreciate your support.

Perfect
Top quality sterile grains and I have not had one bad bag! Good product!
North Spore
Thanks for sharing, Nathan! We couldn’t do it without customers like you.

Grain bag
I’m continually impressed with North spore and their products they sell. Takes the guess work outa it!
North Spore
Thanks for sharing, Christine! We appreciate you taking the time to share your experience. We're so happy it's all working out for you.

Fantastic
Extremely high quality stuff. These guys at North Spore know their stuff. OMG
North Spore
Thanks for the great review! Please reach out if you ever need anything.