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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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North Spore Grain Bags
The best grain bags available!
North Spore
Thanks, Matthew! We really appreciate your support.

You pay for what you get.
I feel like there are a lot of cheaper options, but north spore is very clean and consistent when it comes to their product. I will be a continuing customer.

Great stuff
Works great and haven't had any issues so far... You folks are awesome and I look forward to doing more business with you in the near future. Thank you!!! Mush love!!!

Great
Thank you product is great
North Spore
Thanks for the great review, Conor! We really appreciate your support!

They are producing beautifully
It was great super sterile and it gives me plenty to work with
North Spore
Thanks, Kohlton! Our team is here if you need anything!

Grain bags
My experience with Northspore has always been amazing. Great customer service and they will make it right if a back came contaminated.
North Spore
We really appreciate the kind review, Ivan! The team is here to help if you ever need anything.

Grain bag review
My experience was an overwhelming success! Thank you. Your mixture is obviously very close to my formula, after watching the colonization rate, and results. The addition of millet makes the total difference from the other products available on the market. And, this saves so much time and energy preparing your own, at home. Kudos, and Thank you!!
North Spore
We're so glad everything is working out for you, David! The team is here to help if you ever need anything.

Top of your game
Very professional company that has great customer support
North Spore
Thanks so much, Benjamin! We really appreciate the kind review.

Flawless Grain
Colonized perfectly. No contamination problems. Great size. Cost is higher, along with shipping to my region. Only grain to work for me perfectly though. If you don’t have the equipment and self-skill this is a go-to.
North Spore
Thanks, Charles! We're so glad everything is working out for you. The team is here to help if you ever need anything.

Great grain bags
After dozens of purchases, I've only had one grain bag have contam. North spore replaced it with no hassle. Great product with predictably good results
North Spore
Thanks for sharing, Jillian! The team is here to help if you ever need anything.