Organic Sterilized Grain Bag with Injection Port












Certifications | USDA certified organic |
Media | Organic wheat & millet mix |
Moisture content | Hydrated to a target of 50% |
Bag weight | 3 lbs |
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Our best-selling organic sterilized grain spawn bag was formulated by mycologists to maximize the speed and size of your mushroom grow. Each spawn bag contains our proprietary 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 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.
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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Millet worked great
Order came as specified. I innoculated and detected mycelium 9 days later. At 28 days the bag is just under 1/2 colonized.

Grain bags
Awsome....great guys to buy from

Grain bag
Well I’ve ordered mushrooms supplies from just about everyone and they were all full of ****. I saw your add you were my last hope. I inoculated bag after refrigerating for 48yr. and nothing for 2.5 weeks . One day I finally gave up and WALA there was mycelium! Just waiting for 100% and I’ll mix with 8lb. bag of substrate I also ordered from you. If it goes well I’ll definitely be counting on North Spores It’s been 1yr. of trial and error and not a single shroom I’m trying for 1st time for alcoholism and depression, PTSD. I have 0 experience so it’s my fault . Tom Higdon

Packed with Care
I would definitely order from you guys again. Delivery was fast and packed in a user friendly package. Tracking was accurate and very convenient from the moment it shipped.
High quality and reliably sterile
I have ordered and used the grain bag product several times. Every time it has arrived in great condition and perfectly sterile.

Amazing
Love this grain bag so much. Got one to compare against another brand I got and this one colonized much quicker than the other bag I got. Love it so much that I’m now getting 12 more grain bags from North Spore. Thanks for making such a great product! :)