Mushroom Cultivation: The Three Stages from Compost to Harvest

Fungiculture scales from kitchen counter to commercial warehouse. The process has three non-negotiable phases—master each, and mushrooms follow.

1. Compost Preparation (Substrate)

Goal: selective nutrient base for mushroom mycelium, hostile to competitors.

• Ingredients: Straw/horse manure + gypsum + nitrogen supplements (or synthetic: straw + poultry manure + gypsum).
• Phase I (outdoor, 7–14 days): Windrow, wet, turn daily. Microbial heat hits 70–80°C—pasteurizes, selects thermophiles.
• Phase II (tunnel, 6–10 days): Pasteurization (56–60°C, 8+ hrs) kills pests/nematodes. Conditioning (45–52°C) finishes ammonia conversion. Cool to 25°C for spawning.

2. Spawning (Inoculation)

Mycelium expansion from grain spawn into compost.

• Spawn: Sterilized grain (millet, rye, wheat) + pure culture mycelium. Incubate 14–21 days at 24°C.
• Spawning: Mix spawn into compost at 0.5–1% by weight. Uniform distribution critical.
• Spawn run (14–21 days): 24–25°C, high CO₂, 95% RH. Mycelium colonizes fully. White "matting" signals readiness.

3. Casing, Pinning, Cropping

• Casing: 4–5 cm peat/limestone (pH 7.5) layer over colonized compost. Microclimate for primordia. No nutrients needed.
• Pinning: Drop temp to 16–18°C, introduce fresh air (CO₂ <1000 ppm), light (indirect), RH 85–90%. Tiny pins emerge 7–10 days.
• Cropping: Harvest flushes (breaks) every 7–10 days. 3–5 day pick window per flush. 3–5 flushes typical. Total cycle: 60–90 days from spawn.

Key Controls

Hygiene (HEPA, sterilization), climate automation, strain selection (commercial vs. wild), pest monitoring (sciarids, phorids, mites).

Mushroom farming is precision microbiology. Skip a step, and contaminants win. Follow the phases, and the fungi do the work.