Boomr Bag Sterile Manure Substrate

Our best-selling Boomr Bag is a sterile 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 your Boomr Bag in monotubs, outdoor beds, or to grow mushrooms from the bag in a humidity-controlled grow room or Martha setup!

We recommended 1 lb of colonized grain spawn for every 5 lbs of Boomr Bag sterile substrate. (Higher inoculation rates may improve your success.)