Mushroom Growing Light Cycle Calculator
Calculate optimal daily light and dark cycle for mushroom fruiting.
Covers oyster, shiitake, lion mane, and reishi with recommended hours and light intensity.
Light plays a surprising role in mushroom cultivation. While mushrooms do not photosynthesize like plants, many species use light as a directional cue (phototropism) and as a trigger to initiate fruiting body formation.
Light Requirements by Growth Stage
| Stage | Light Needed | Duration | Purpose |
|---|---|---|---|
| Inoculation | None (total dark) | 0 hours | Prevents contamination, no benefit from light |
| Colonization | None to minimal | 0–4 hours | Mycelium grows in dark; some species benefit from brief light exposure |
| Primordia formation | Moderate | 10–12 hours | Light triggers pinning in many species |
| Fruiting | Moderate | 10–12 hours | Directs growth upward, improves cap formation |
| Harvest | N/A | N/A | Harvest before spore drop |
Species-Specific Light Requirements
| Species | Colonization Light | Fruiting Light | Light Intensity | Spectrum |
|---|---|---|---|---|
| Oyster (Pleurotus) | 0 hrs | 10–12 hrs | 500–1,000 lux | 6,500K (daylight) |
| Shiitake (Lentinula) | 0 hrs | 10–12 hrs | 500–1,000 lux | 6,500K |
| Lion’s Mane (Hericium) | 0 hrs | 10–12 hrs | 200–500 lux | 5,000–6,500K |
| King Oyster (Pleurotus eryngii) | 0 hrs | 12 hrs | 500–1,000 lux | 6,500K |
| Maitake (Grifola) | 0 hrs | 10–12 hrs | 200–500 lux | 5,000–6,500K |
| Reishi (Ganoderma) | 0 hrs | 12 hrs | 500–1,000 lux | 6,500K |
| Button/Cremini (Agaricus) | 0 hrs | 0 hrs | None needed | N/A |
| Enoki (Flammulina) | 0 hrs | 4–8 hrs | 100–300 lux | Low intensity OK |
| Pioppino (Agrocybe) | 0 hrs | 10–12 hrs | 300–500 lux | 6,500K |
Worked Example — Blue Oyster Mushrooms in a Fruiting Chamber
Species: Blue Oyster (Pleurotus ostreatus var. columbinus). Stage: Fruiting. Light on: 12 hours. Light off: 12 hours. Intensity: 800 lux. Spectrum: 6,500K daylight LED.
Schedule: Lights on at 6:00 AM, lights off at 6:00 PM. Use a simple plug-in timer — no fancy controllers needed.
At 800 lux, a standard 10W LED shop light positioned 2–3 feet from the fruiting blocks provides adequate intensity for a small fruiting chamber (2–4 sq ft). For larger rooms, calculate:
Lux at Distance ≈ Luminous Flux (lumens) ÷ Area (m²)
A 10W 6,500K LED produces about 800–1,000 lumens. At 1 meter from a 1 m² growing area, that provides 800–1,000 lux — perfect for most species.
Daily Light Integral (DLI)
Some advanced growers track DLI instead of simple on/off hours:
DLI (mol/m²/day) = PPFD (µmol/m²/s) × Hours × 3600 ÷ 1,000,000
For mushrooms, DLI of 1–4 mol/m²/day is sufficient. This is far less than plants, which need 12–40+ DLI.
Electricity Cost Estimate
A 10W LED running 12 hours/day:
- Daily: 0.01 kW × 12 hrs = 0.12 kWh
- Monthly: 0.12 × 30 = 3.6 kWh
- At $0.12/kWh: $0.43/month — negligible cost.