Vermiculite - [Fine Grade]

Fine (small) sized vermiculite. Fine vermiculite is commonly used as an ingredient in mushroom substrate cakes, such as PF-tek style cakes. The PF tek recipe is: 2 parts fine vermiculite, 1 part brown rice flour, 1 part H2O.

Sold in ½ gallon increments.

Coarse grade vermiculite is available here.