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North Spore

‘Boomr Bag’ (5 lb) Manure-Based Sterile Mushroom Bulk Substrate | Maximum Yield Formula | Made in USA | Grow Dung-Loving Mushrooms | North Spore

    • Based on 1,104 reviews
Condition: New
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Availability: In Stock.
Fulfilled by North Spore Mushroom Company
Arrives May 7 – May 9
Order within 1 hour and 27 minutes
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Features

  • INCREASE YOUR YIELD: Our best-selling Boomr Bag is a sterile manure-based bulk mushroom substrate formulated by mycologists to increase the yield of your grow.
  • PREMIUM MANURE BLEND: It features a proprietary blend of composted horse manure, coco coir, and several quality substrate supplements (although we keep the exact blend a secret!)
  • TRUSTED BY GROWERS: Over several years, Boomr Bag has been perfected for dung-loving mushroom species and is widely-trusted by mushroom growers. Note: Substrate is hydrated to field capacity.
  • FOR EVERY TYPE OF GROWER: 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.)
  • STORAGE: 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.
  • BEST PRACTICES: We recommend clean hands, latex or nitrile gloves, and sterile technique when using Boomr Bag to reduce the introduction of contaminants. It is also best practice to wait a minimum of 1 week after arrival before using sterile substrates to ensure they were not compromised during transit.

Brand: North Spore


Style: Sterile substrate


Item Weight: 5 Pounds


Item Volume: 4.75 Liters


UPC:


Product Dimensions: 8 x 5 x 5 inches


Item Weight: 5 pounds


Manufacturer: North Spore


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: May 7 – May 9

Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

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Top Amazon Reviews

    • It works as advertised.
Very satisfied with the product. It has colonized very quickly and so far, no contamination. Thank you guys.
Reviewed in the United States on March 1, 2025 by David Kalb
    • High quality and looks well made.
Fast shipping and very clean and high quality from its box and provided instructions to the actual bag all top notch quality, I will update about the results but so far I am happy with my purchase and definitely purchase more of this products of this seller. Highly recommended
Reviewed in the United States on November 1, 2024 by mehran
    • Best pre-pasteurized substrate I've found.
I switched to boomr bags after being unsatisfied with other pre-pasteurized substrates and mixing and sterilizing my own. It's not cheap, but the end result is superior. Keep bag for at least a week before using to check for contam. North Spore will replace for free any contaminated bags if you contact them. I've never seen a contaminated bag even after over 20 orders, but I have had to get north spore to replace a grain bag which they did hassle-free. Just take a pic of the contaminated and the lot number sticker on bag and email them. For anyone saying this substrate doesn't work for manure lovers, I'd say you just don't know how to grow mushrooms. A lot of people contaminate batches themselves without realizing it. The bag may come too wet or dry. Too dry, just spray with distilled water during mixing with spawn in sterilized room. Too wet (you can tell if water separates from substrate and you can see liquid in bag) let it dry out by spraying breather patch with alcohol and unfolding bag a little and let sit a few days. Always spray breather port with alcohol before handling or moving it from box. Airborne bacteria can get pulled into bag from patch. ... show more
Reviewed in the United States on January 21, 2023 by Travis Lee
    • Comes pre contaminated!
Have bought 3 times and was treated to pre contaminated substrate. I’ll stick with m*sh c*cult from now on.
Reviewed in the United States on March 20, 2025 by Mills
    • Boom bags
Moisture Contant, drier than I would’ve liked, but usable. This product is used to grow mushrooms. i’ll give it four stars
Reviewed in the United States on January 10, 2025 by gary hance
    • Very happy
This sat for weeks before use, no issues with leaks or any kind of bad stuff growing in it. Moisture content was perfect even after sitting so long. I added this to two separate bags of mycelium that was growing in other substrate bags, allowed a few days to mix and colonize a bit more, then dumped into growing trays that had lids and air vents. Mycelium fully colonized within a week, thick white carpet of fuzz was gorgeous and happy. Moisture content stayed perfect throughout growing cycle. Absolutely no sign of contamination or mold or anything bad even after several months. Would recommend and buy again ... show more
Reviewed in the United States on October 24, 2023 by Svz
    • marginal value - overall yields very low due to contamination issues
marginal value, due to contamination problems: at least one bag was contaminated with a fungus that was starting to propagate prior to use; at least two other bags in the same order had contamination issues; opt for substrates that are less prone to contamination; if you are growing dung-loving mushrooms, then perhaps look for other products or DIY on the pasteurization ... show more
Reviewed in the United States on April 21, 2025 by Amazon Customer
    • Northport is bae, mush love
research purposes, and microscopy purposes only
Reviewed in the United States on January 14, 2025 by Adam

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