What is the best substrate for Psilocybe cubensis?

Coco coir and vermiculite (CVG) is the most popular bulk substrate for P. cubensis. It is easy to prepare, pasteurizes quickly with boiling water, has a low contamination rate, and produces excellent yields. Other good options include manure and straw, though these require more careful preparation.

How much substrate do I need per litre of grow container?

A standard guideline is to fill 50–60% of your container with prepared bulk substrate, targeting a depth of 10–15 cm. For a 66-litre tote, this means roughly 33–40 litres of prepared substrate including grain spawn and bulk mixed together.

What is field capacity for substrate?

Field capacity means the substrate holds the maximum amount of water without excess dripping out when squeezed firmly in your fist — just one or two drops should fall. Too dry slows colonization; too wet causes anaerobic conditions and contamination. Correct field capacity is one of the most critical factors in substrate preparation.

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