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.