Mass Mycology Sterile Manure Substrate

Maximize your mushroom yield!

Our best-selling Substrate 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 cow manure, coco coir, and several quality substrate supplements.

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 substrate bags 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 substrate bags. (Higher inoculation rates may improve your success.)