PF Tek is a method of mushroom cultivation pioneered by Robert McPherson, aka Psylocybe Fanaticus. This technique (Tek) originally utilized organic rye berries, but later included brown rice flour and vermiculite. The substrate is sterilized in half pint wide mouthed canning jars by boiling or pressure cooking, with a layer of dry vermiculite as a filter agent to keep out competing bacteria and fungus. The sterilized "PF jar" is then injected with a solution containing spores and water from a syringe, creating a one step procedure for reliably growing mushrooms indoors.
Psylocybe Fanaticus was the business name of Robert McPherson, the creator of the PF Tek. The PF Tek can be used to grow a wide variety of mushrooms including the edible species shaggy mane, lion's mane, the bioluminescent species Panellus stipticus, and various species of psilocybin mushrooms.
Strengths and weaknesses
PF Tek is a popular method for home cultivation because it is easy, simple, inexpensive and reliable. The materials needed are cheap and widely available. Jars can be sterilized by boiling or with a pressure cooker. Although sterile technique is required when inoculating, risk of contamination from airborne spores or bacteria is small because air exposure is minimal and the layer of vermiculite which acts as a filter.
More experienced growers may not use PF Tek due to its low yield, and high labor input required when compared to other methods, like Monotubs. The use of a spore syringe also has its drawbacks. Because spores are a mix of genotypes, it is impossible to select mycelium that colonizes fast and produces high yield. The use of liquid culture can minimize the downsides of using spore syringes, but yields are still low compared to other methods.