Maximize your mushroom yield! 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. Features & benefits: Made entirely from organic materials pH balanced 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. Spawn to bulk ratio: We recommended mixing 1 colonized grain spawn bag with 2-3 Boomr Bags. (Higher inoculation rates may improve your success.)