Cultivation
Sterilization
The single most-asked-about step. Why pressure matters more than time, and where most home setups go wrong before the autoclave even closes.
Sterilization is the foundation of clean cultivation. Pasteurization is good enough for fast-colonizing species on bulk substrate; for grain spawn, pressure cooking or autoclave-grade sterilization is non-negotiable.
Pressure, not just time
15 PSI gives you 250°F (121°C). Below that, common bacterial endospores survive any reasonable time. The most common home failure is a pressure cooker that leaks just enough to never reach steady-state pressure, which looks like sterilization but is closer to a long bake. Calibrate the gauge, check the gasket, and time from full pressure, not from when you turned on the burner.
Workflow
- ▸Pre-soak grain to field capacity before bagging.
- ▸Bag with a 0.2 micron filter patch and inject port.
- ▸Sterilize at 15 PSI; longer for larger bag sizes.
- ▸Cool fully in the chamber before opening to avoid pressure shock contamination.