How to Use Vermiculite With Mushrooms?

By itself, Vermiculite has a neutral pH and is therefore not suitable as a sole substrate for growing mushrooms that need slightly acidic pH substrate. However, it can be combined with other materials to achieve the proper balance.

Mushrooms need three elements to thrive: water, a growing medium, and aeration. Vermiculite is an essential element that helps promote the healthy propagation of many different types of mushroom cultivation. It is a popular add-on to many grow kits that helps to create bigger, healthier mushrooms.

Vermiculite is also an excellent casing layer as it helps mushrooms spores to produce fruit. Casing layers are beneficial for several reasons. When combined in a substrate with brown rice flour, vermiculite can provide a contamination barrier that will also protect the spores from degradation while growing.

What Grade Vermiculite for Mushrooms?

Fine grade vermiculite absorbs and quickly releases moisture. So fine (small) sized 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.