BRF Jars & PF Tek Mushroom Substrate

Sterilized BRF jars are the easiest way to start growing mushrooms at home. Each jar contains a precisely blended mix of organic brown rice flour and vermiculite, pressure sterilized in our commercial autoclave, and sealed with a modified lid featuring a self-healing injection port and gas exchange filter. Just inject your spore or liquid culture syringe and incubate — no pressure cooker or substrate prep required.

The PF Tek method was developed in 1992 by Robert McPherson and remains one of the most popular mushroom cultivation techniques for beginners. The brown rice flour provides a rich nutrient base for mycelium, while vermiculite retains moisture and creates air pockets that promote healthy colonization. Our BRF jars are optimized for this technique with the ideal flour-to-vermiculite ratio and hydration level.

How it works: Inoculate your BRF jar through the injection port with 1-2 cc of spore or liquid culture. Incubate at 75-81°F for 3-5 weeks until fully colonized (the jar turns completely white). Then birth the colonized cake into a fruiting chamber with perlite for humidity. Expect your first mushrooms within days of fruiting.

Why our BRF jars? Every jar is sterilized in a commercial autoclave — not a home pressure cooker. The modified lids include a self-healing injection port for clean inoculation and a filter patch for gas exchange, so you can inoculate in a flow hood or still air box with minimal contamination risk. Available in multi-packs for larger grows.

Compatible with all species. BRF jars work with virtually any mushroom species and are especially well-suited for beginners. Pair with our pre-poured agar plates for strain isolation, or our all-in-one grow bags if you want to skip the fruiting chamber step entirely.