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‘Boomr Bag’ Manure-Based Sterile Mushroom Bulk Substrate


















Media | Horse manure mix |
Moisture content | Hydrated to field capacity |
Bag weight | 5 lbs |
Maximize your mushroom yield!
Our best-selling Boomr Bag is a sterile manure-based bulk mushroom substrate formulated by mycologists to increase the yield of your grow. It features a proprietary blend of composted horse manure, coco coir, and several quality substrate supplements (although we keep the exact blend a secret!) Over several years, it has been perfected for dung-loving mushroom species and is widely-trusted by mushroom growers. Note: Substrate is hydrated to field capacity.
Use Boomr Bag in monotubs, filter bags, and outdoor beds. Or, grow mushrooms from the bag or tray in a humidity-controlled grow room or Martha set up.
Spawn to bulk ratio:
We recommended mixing 1 colonized grain spawn bag with 2-3 Boomr Bags. (Higher inoculation rates may improve your success.)
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- We recommend clean hands, latex or nitrile gloves, and sterile technique when using Boomr Bag to reduce the introduction of contaminants.
- Be sure to mix colonized grain spawn thoroughly into your substrate.
- It is best practice to wait a minimum of 1 week after arrival before using sterile substrates to ensure they were not compromised during transit. Rest assured that your purchase is 100% guaranteed. If your substrate was compromised, we will replace it.
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Boomr 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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Our Boomr Bags are sterilized in a commercial-grade autoclave. Sterility is verified using biological indicators and temperature sensors.
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North Spore's products shall be used only for lawful purposes. North Spore does not condone Psilocybin (Psilocybe cubensis) or hallucinogenic (magic) mushroom growing in jurisdictions where it is currently illegal.
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- Reviews
- Questions
Thank you for submitting a review!
Your input is very much appreciated. Share it with your friends so they can enjoy it too!

Always works
Good as it always is
North Spore
Thanks, Neil! We really appreciate your support. If you need help with anything, please reach out.

Great Sub!
Very nice sub, I got four zips off of the first flush. I had an issue with a bag, customer service was great, and they sent me a bag out asap.
North Spore
Thanks for the great review, Dustin! Please reach out if you ever need anything.

Great substrate
I've been using this sub for a few years now. Consistently good quality, always great yields
North Spore
Thanks, Jillian! We really appreciate your support.

Excellent
Great growth
North Spore
Thanks for sharing, Kristine! We appreciate you taking the time to share your experience.


Best Sub Out There!
Best sub mix I've ever used, if you give it a try you won't go back to any other or even mixing your own :)
North Spore
Thanks so much, Beverly! We really appreciate the kind review.

Excellent
Not a problem everything worked as it should was totally satisfied. looking forward to doing business with you guys again.
North Spore
Thanks, Ronald! The team is here to help if you ever need anything.

Top Notch
Awesome products with great customer support. If there's ever any problems with there products, they take care of it and fast!
North Spore
Thanks for the great review, Adam! We really appreciate your support.

Here comes the boom
These bags bring the boom; happy with my purchase! Will order more soon!
North Spore
Thanks for the great review, Ephraim! We really appreciate your support.

A gift for a friend
My friend was super excited to see how well this substrate performed! The growth rate and vigor of the mushrooms is exceptional. He has had no issues with contamination. It will be fun to enjoy some mushrooms with him once he is able to harvest them.
North Spore
Thanks for sharing, Lisa! We appreciate you taking the time to share your experience.

As far a manure goes... this was perfect.
The items are always as described and if there are ever any issues (which are bound to happen in this industry) the customer service is where North Spore shines.
North Spore
Your review made our day, Joe! Please reach out if you ever need anything.