Sterile Substrate 8-Pack ‘Boomr Bag’ Manure-Based Sterile Mushroom Substrate

Sterile Substrate 8-Pack Boomr Bag Sterile Manure Substrate

Sterile Substrate 8-Pack 'Boomr Bag' Sterile Manure-Based Mushroom Substrate

Sterile Substrate 8-Pack ‘Boomr Bag’ Manure Sterile Bulk Substrate

8-Pack ‘Boomr Bag’ Manure-Based Sterile Mushroom Substrate

Name: 8-Pack ‘Boomr Bag’ Manure-Based Sterile Mushroom Substrate
Brand: North Spore
SKU: EQUIP-BOOMR-8CT
Price: 111.95 EUR
Availability: InStock
Rating: 4.65 (136 reviews)

€111,95

Our best-selling Boomr Bag is a sterile manure-based bulk mushroom substrate formulated by mycologists to increase the yield of your grow. Over several years, the recipe has been perfected for dung-loving mushroom species and is widely-trusted by mushroom growers. Use Boomr Bag in monotubs, filter bags, and outdoor beds. Or, grow mushrooms from the bag or in a tray using a humidity-controlled grow room or Martha setup.

Choose Your Size

Single Box (5 lb)

$28.99/bag

Our best-selling substrate

8-Pack (Best Value)

$16/bag

Save 42% by stocking up

Trusted by 350K+ Growers

Money Back Guarantee

USDA Certified Organic

Elevate your indoor mushroom cultivation with North Spore’s 8-Pack ‘Boomr Bag’ Manure-Based Sterile Mushroom Substrate. This professional-grade substrate is engineered for optimal mycelial colonization, providing a foundation for robust and productive mushroom yields.

Each ‘Boomr Bag’ contains a carefully formulated, manure-based substrate blend. This rich organic material supplies essential nutrients, promoting vigorous growth and ensuring the development of healthy, dense mushroom flushes.

Our substrate undergoes a precise sterilization process, eliminating competing organisms. This critical step minimizes contamination risk, offering a clean and reliable environment for successful mushroom development, ideal for monotubs.

The convenient 8-pack bundle ensures an ample supply for multiple cultivation projects or larger setups. Designed for ease of use, these sterile substrate bags integrate seamlessly into various indoor growing systems.

For detailed instructions on utilizing the ‘Boomr Bag’ substrate effectively in your specific cultivation method, please refer to our comprehensive guides on the North Spore website.

Why It's Dope

Made entirely from organic materials
Balanced pH with a complex nutrient profile
Proven vigorous mycelial growth
Fast colonization and higher yields
Increased aeration and moisture retention
Hydrated to field capacity

Boomr Bag is made from a blend of quality local, organic, and non-GMO materials including a proprietary blend of composted horse manure, coco coir, and several quality substrate supplements (although we keep the exact blend a secret!) Unlike other substrates that contain harmful additives, you can rest assured that your grow will be natural and chemical free.

How to Use

Spawn to bulk ratio

We recommended mixing 1 colonized grain spawn bag with 2-3 bags of sterile substrate. (Higher inoculation rates may improve your success.)

Best Practices

We recommend clean hands, latex or nitrile gloves, and sterile technique when using sterile substrate 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.

Storage

Sterile substrates should be stored at room temperature out of direct sunlight. No refrigeration is necessary. They can also be stored for several months before use.

Made Right, Guaranteed

Sterilized in a commercial-grade autoclave for consistent results
Multiple bags from every batch tested in our state-of-the-art lab
Verified using biological indicators and temperature sensors
Backed by our 100% Guarantee — if it’s not sterile, we’ll make it right

Notice

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.

CA Prop 65 Notice

All-in-One Bags or Monotub Bins: Which Mushroom Growing Method is Best for You?

Grow Right

Organic Sterilized Grain Bag with Injection Port (+€20,95)

Add an extra grain bag

Syringe Multiplier & LC Kit (+€23,95)

Multiply any spore or syringe into 30 syringes!

"Boomr Bin" Monotub (+€26,95)

The best grow chamber for bulk substrate

NocBox Still Air Box (+€65,95)

Reduce contaminants when you mix or inject substrate

Nitrile Gloves (+€12,95)

Stay clean, stay sterile

Sterile Substrate FAQs

Choose Boomr Bag for massive flushes of dung-loving species, CVG for versatile bulk grows and great moisture retention (great for beginners), and Wood-Lovr for wood-loving species like oysters, lion’s mane, and reishi. Each is optimized for the best yield and growth rate in its category.

Keep bags at room temperature and out of direct sunlight. Substrates can be stored for several months, and grain bags should be used within a few weeks for best results.

We sterilize our products in commercial autoclaves and test every single batch for bacterial growth so you know the product is sterile when you receive it. And if the bag is compromised in any way during shipping, our 100% guarantee means we'll make it right

While you can grow directly in the bag, the best way to grow with bulk substrate is to to use a monotub.

A general rule is 1 colonized grain bag for every 2–3 substrate bags. Higher spawn ratios often speed up colonization and reduce the risk of contamination.

Grain bags are for colonizing mycelium, while sterile substrates (like Boomr Bag, CVG, or Wood-Lovr) are for fruiting mushrooms. You’ll inoculate the grain bag first, then mix the fully colonized grain with your chosen substrate to begin fruiting.

Cluster of brown-capped mushrooms with long, light-colored stems against a white background.

Lab-Crafted. Grower-Approved.

Get the most out of your grow with our premium sterilized substrates—formulated, hydrated, and sterilized to deliver consistent, high-yield results. Each batch is crafted from organic ingredients and sterilized in a commercial-grade autoclave for contam-free performance. Whether you’re spawning to bulk for the first time or fine-tuning advanced grows, our substrates provide the perfect foundation for strong, healthy mycelial growth.

The right mix for every grow

Our substrates start with premium organic ingredients—nutrient-rich, finely milled, and perfectly balanced for ideal texture, aeration, and moisture. Each blend is designed by mycologists to support vigorous mycelial growth and consistent, high-yield harvests. Built on quality ingredients and precise formulation, they’re the foundation every successful grow begins with.

Reviews

5 stars: 114 (84%)
4 stars: 11 (8%)
3 stars: 4 (3%)
2 stars: 0 (0%)
1 star: 7 (5%)

Looks great!!! Will see in a few weeks when i have new grain spawn mixed in!

Contamination i would not buy again from Northspores they have lost me as a customer

Always high quality from North Spore. Never had an issue

As always northspore went above and beyond I highly recommend northspore for all ur mycology supplies I been dealing with them for about a yr and absolutely no complaints

Fast. Thank you.

I can write a week long review and still never expressed how deeply thankful I am to North Spore for their amazing products. You will not find a better product on the market.

Good product n the bulk is perfect thanks again

2 out 8 are defective

These work well if you want an easy and small grow. However, out of the 8 I ordered, 2 turned green after a few days. The rest are fine so far and I already innocuate the other 6. You would say 6 out of 8 is decent, but these bags are not cheap.

Thanks for your review, Mary! If you ever receive a contaminated bag, please don't hesitate to reach out to our customer service team at info@northspore.com. We're always happy to help!

Great yields and consistent well pastirized substrate without contamination issues

Thanks for sharing, Justin! We really appreciate your support!

Arried in oerfect confition

Great fast delivery

Thanks for sharing, John! Please reach out if you ever need anything.

10/10

This is a awesome mix, switched from ANOTHER Companies substrate,cvg ,lots of nutrition, more full flushes,bigger fruits and flavor

Two bags broken 💔 Sadness 😔. Happened in shipping. And they replaced it! Epic, thanks 😊 🙏

Best dung lovong sub around

Quick shipping. They are a great product.

Was delivered on time and the product was what I purchased. Cant wait to use it.

Perfect healthy mix

Perfect healthy mix for dung loving mushrooms ‍🟫

Love these guys!

Northspore killed it again what an outstanding company my substrate shipped the very next day ordered after hrs and anytime I have a question or concern northspore is there to help I order all mycology supplies from northspore and will continue to do so awesome company.

Great product support if you notice contamination

Have used several times with great success, if you notice contamination before you use, Northspore support does an amazing job crediting you to buy more. Will definitely keep supporting.

Always the best

I’ve been ordering from Northspore for years and always had great results.
Recently tried the coffee and like their other products, I wasn’t disappointed.
Thank you so much! Rick Bazauri

Thanks for sharing, Rick! We appreciate you taking the time to share your experience.

Happy Customer

Super fast shipping, as always! Sturdy, beautifully designed packaging/shipping container. Superior product!

Good substrate no contam but felt like the bags were just thrown in the box

Arrived on time right on my porch. Thanks

Very fresh ,clean will buy again

Thanks for sharing, Aaron! We appreciate you taking the time to share your experience with everything.

Love this substrate it's never let me down.

Thanks, Darren! We are so glad the substrate worked out! Our team is here if you need anything!

Simply the BEST!

North Spore has never let me down! Excellent customer service and really nice substrate for my dung loving mushrooms. I have been working with them for about three years now.

Thanks so much for the support, Kelly! We couldn’t do it without customers like you. We're so glad everything is working out for you!

Great product and flushes. Moisture levels we great.

Very good service

Other than one bag getting contaminated. (Follow the directions prior to using it) I have to say it has been nothing but great quality. Once in a while you will have a bad bag. (Which is rare.)