Hardwood Sawdust Substrate for Reishi

How do I prepare it?

Mix sawdust with brans and gypsum, hydrate to 60%, bag and sterilize at 15 PSI for 2.5 hours.

1. Weigh 3.6 kg hardwood sawdust (oak, maple, or alder).
2. Mix with 320 g wheat bran, 80 g rice bran, and 50 g gypsum.
3. Add water to reach 60% moisture (squeeze test: 1–2 drops).
4. Fill filter-patch grow bags with 2.0–2.5 kg substrate.
5. Sterilize at 15 PSI (121 °C) for 2.5 hours.
6. Cool 8–12 hours before opening.
7. Inoculate with Reishi grain spawn at 10%.
8. Incubate at 25–30 °C in darkness for 30–45 days.
9. Cut slit in bag and initiate fruiting at 24–28 °C, 80–90% humidity.
10. Harvest when brown spore dust is released (60–90 days fruiting).