Bulk Pelletized Gypsum

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  • Regular price $0.99


Sold in increments of 50 grams so that you can order close to the exact amount needed for your next batch of coco coir/vermiculite/gypsum substrate. To minimize packaging, the total quantity you order will come in a single bag, or in increments of 500 grams if you order more than 500 grams. 

Questions about how much gypsum to order? Check out the substrate calculator here

Our gypsum comes in a pelletized form.  This makes it much easier to work with because it creates less dust and mess. 

Gypsum is a highly recommended ingredient for grain spawn and monotub substrate for two reasons:  

  • Gypsum provides calcium and sulfur, two essential nutrients that mycelium crave. 
  • Gypsum helps to prevent grain and substrate from clumping (sticking together).

For grain spawn, 2% (by weight) of gypsum is typically added. For coco coir/vermiculite/gypsum substrate, 5% (by weight) is typically added.