Master's Mix

Master's Mix is the standard substrate for wood loving mushrooms that need more nutrition than wood alone. It is a mix of hardwood sawdust and soy hulls, usually half and half by dry weight.

What you use it for:

Master's Mix works well for lion's mane, shiitake, chestnut mushroom, pioppino, nameko and reishi. Oyster mushrooms do not need it; they grow perfectly well on pasteurised straw, coffee grounds or wood pellets.

Preparing it:

1. Mix the sawdust and the soy hulls together dry.
2. Add water until you reach about 60 percent moisture. You can tell by squeezing a handful; a few drops should come out, no more.
3. Fill a grow bag with a filter to about two thirds.

Sterilise, do not pasteurise:

The soy hulls make Master's Mix so nutritious that bacteria and moulds are just as happy on it as the mycelium. Pasteurising is therefore not enough. Sterilise the filled bags for 2 to 2.5 hours at 15 PSI in a pressure cooker or autoclave and let them cool down completely before you inoculate.

Inoculating:

Work in a clean area with disinfected hands and surfaces. Mix roughly 1 part spawn to 10 parts substrate and close the bag again with the filter or micropore tape.

Colonising:

Keep the bag in the dark at the colonising temperature of the species, usually between 20 and 25 degrees. Depending on the species it takes two to six weeks before the substrate is completely white. After that you can cut the bag open and start fruiting.