The most popular and reliable mix for a casing layer is the 50/50 blend of Peat Moss and Vermiculite, known for its excellent moisture retention, aeration, and support for surface mycelium growth.
To be effective, this casing layer must be properly hydrated typically between 40% and 50%. Too dry, and your mycelium may stall. Too wet, and you risk contamination or suffocating the developing pins. That’s where our Casing Layer Calculator helps.