Autumn shiitake mushrooms are cultivated from September to November. After the Start of Autumn, the temperature difference between day and night grows prominent — cool nights paired with warm days, which creates ideal conditions for mushroom bud formation and growth. Mushroom logs will sprout abundant buds in this period. Below are key management tips for the autumn fruiting stage:
1. Regulate temperature and temperature difference
The optimal temperature inside the mushroom shed is 13–18℃.
- When temperature stays above 20℃: Unfold plastic films for ventilation and heat dissipation in the morning and evening.
- When temperature drops below 12℃: Open shade nets at noon to let in sunlight for warming.
Suitable temperature plus proper temperature difference jointly boost bud differentiation. You can adjust ventilation, shade nets, or soak, inject and spray water on mushroom bags to lower their surface temperature and stimulate primordia growth. Note that a mere temperature difference without proper ambient temperature cannot yield good fruiting.
2. Control relative humidity
- Keep humidity at 85%–90% to help buds form and survive.
- When buds grow to 1 cm long: Cut down water spraying and increase ventilation to improve mushroom quality.
- When mushroom caps reach 2 cm: Stop frequent spraying, and let mushrooms absorb moisture from the bags. This produces shiitake with bright color, firm flesh and good transport resistance.
- After budding: Maintain shed humidity below 80% to avoid dark-colored or waterlogged mushrooms. For thick-fleshed high-quality mushrooms, keep humidity around 60%.
- Spray water only in cool morning and evening; midday spraying will make mushroom caps turn rusty red.
3. Optimize ventilation and light
- Thick, spongy and elongated stipes mean poor ventilation. Enhance air circulation timely.
- Pale yellow caps with thin edges indicate insufficient light. Partially remove shading materials or plastic films to boost light and ventilation.
4. Thin mushroom buds reasonably
Too dense buds affect growth. Clear weak buds and scatter clustered ones. Keep 10–15 healthy buds on each mushroom bag for balanced growth.
5. Clean up and rejuvenate mycelium after harvest
Right after picking, remove residual mushrooms and roots from the bags. Reduce watering and lower humidity to restore mycelium vitality. It takes 15–20 days for mycelium to recover. When the bags turn firm and mushroom bases become reddish brown, you can start water injection to induce buds for the next harvest.