🍄 Shiitake Fruiting Guide (Lentinula edodes)
For 10 lb Supplemented Hardwood Substrate Blocks
Phases, Environmental Control & Harvesting
Shiitake mushrooms fruit in distinct biological phases that require specific changes to temperature, humidity, light, and fresh air exchange (FAE). Managing these phases properly ensures strong flushes, dense fruit bodies, and multiple successful harvests.
🌱 PHASE 1: Browning & Consolidation (Pre-Fruiting)
Duration: ~4–6 weeks after full colonization
Environment: 70–75°F (21–24°C), dark or low light
What's happening:
- Mycelium finishes internal colonization
- Surface transforms from white to golden-brown (“skin” forms)
- Block densifies and builds fruiting potential
✅ Key Signs to Wait For Before Fruiting:
- Surface fully browned and hardened
- No white mycelial regrowth or exposed substrate
- Block has a firm, leathery feel
- Colonization period complete (minimum 40–45 days)
⏳ Patience is key — premature fruiting = weak or aborted mushrooms.
❄️ PHASE 2: Cold Shock & Soaking (Initiation Trigger)
Timing: After browning is fully complete
Trigger Method: Cold water soak
Procedure:
- Remove block from the bag (or cut large slits if bag-fruiting)
- Submerge in cold clean water (36–45°F / 2–7°C) for 4–12 hours
- Weigh down if necessary to ensure full contact
- Drain thoroughly and allow excess moisture to drip off for 15–30 min
Purpose:
- Simulates rainfall and seasonal drop in temperature
- Triggers primordial (pin) formation
💧 Do not soak early — it may lead to rot or contaminate the block.
🍄 PHASE 3: Pinning & Fruiting
Duration: ~5–10 days
Environment:
- Temp: 55–70°F (ideal: 60–65°F / 16–18°C)
- Humidity: 85–95% RH
- Light: 12 hours/day of indirect light, 6500K (avoid total darkness or direct sun)
- FAE: High — shiitake needs clean, moving air to fruit properly
What to watch for:
- Dark brown bumps appearing across the block (primordia)
- Rapid development into button-sized caps
- Mushrooms double in size every 24–48 hours during peak growth
✅ Keep the block moist, but not soaked. Mist walls or air above the block as needed.
✂️ PHASE 4: Harvesting
Ideal Harvest Time:
- Cap is expanded and slightly convex, not fully flat
- Veil under the cap is torn, but spore drop hasn’t started
- Mushroom feels firm and heavy
- Color is rich brown (strain-dependent)
Harvesting technique:
- Twist and pull gently from the base
- OR cut cleanly with a sanitized knife or scissors
- Avoid damaging nearby pins — harvest in clusters where possible
⛔ Overmature shiitake become spongy, release spores, and are prone to rot.
🔁 PHASE 5: Rest & Re-soak for Future Flushes
After harvest:
- Remove stem stubs and surface debris
- Let the block rest in fresh air for 7–10 days (no soak)
- Re-soak in cold water for another 4–12 hours
- Resume fruiting conditions
📦 A healthy shiitake block can produce 2–4 flushes, with second and third flushes often larger and more attractive than the first.
🧪 Common Issues & Fixes
Issue | Cause / Fix |
---|
No pins after soaking | Block not mature enough – wait longer before next soak |
Mushrooms abort or are misshapen | Insufficient FAE or excess CO₂ — increase airflow |
White fuzz on caps | High humidity and low airflow — adjust FAE |
Mushrooms too pale | Not enough light — ensure indirect 6500K exposure |
Mushrooms drying out early | Low RH — mist more or use humidity tent |
Comments
Hey Josh, I just wanted to say a big thank you for your guide on growing Reishi mushrooms! I’ve been really interested in mycology and health benefits lately, and I think Reishi is one of the most fascinating species out there. Your step-by-step instructions made it super easy for a beginner like me to get started! I never realized how much patience and care goes into cultivating these beauties. I loved the tips on sterilizing the substrate; I think I nailed it! I even got my first little mycelium growth popping up, and I can't express how exciting that is! I appreciate the sections on the health benefits too. It's great to know I'm not just growing some cool fungi, but I'm also tapping into their potential health benefits. Can’t wait to see how they turn out in the coming weeks. Do you have any recommendations for recipes or ways to incorporate Reishi into my diet once I harvest them? Thanks again for the awesome guide! Looking forward to more insights from ShroomSpy. Keep up the great work!
Wow, this guide on growing Reishi mushrooms is fantastic! I've always been curious about cultivating my own medicinal mushrooms, and Josh's step-by-step instructions make it seem totally doable, even for a beginner like me. I love how detailed the guide is, especially the part about the ideal growing conditions and the importance of sterilizing materials. It really makes a difference knowing those little details can impact the health of the mushrooms. I’ve never tried growing mushrooms at home, and I'm excited to give this a shot! The health benefits of Reishi are compelling, and I can’t wait to reap those rewards. Plus, it feels great knowing that I'm taking a hands-on approach to my health. If anyone else is thinking about diving in, I highly recommend this guide. Josh's passion for fungi really shines through, and it’s motivating to see someone knowledgeable sharing their expertise. I'm definitely bookmarking this page and will keep you posted on my progress. Here’s to a bountiful Reishi harvest! Thanks, ShroomSpy, for making mushroom cultivation accessible and fun for everyone!
Hey Josh, I just wanted to give a shout-out for your Reishi growing guide! I've always been fascinated by this fungi's medicinal properties, but I never knew where to start. Your step-by-step instructions made it so easy to follow. I especially appreciated the tips on maintaining proper humidity and temperature—it really helped me avoid the pitfalls I encountered with some of my other attempts. I was a bit nervous about the inoculation process, but your detailed explanation really put me at ease. I've got my logs set up now, and I can’t wait to see how they turn out! It's exciting to think I'll eventually be able to harvest my own Reishi. Do you have any suggestions for recipes or ways to incorporate it into my daily routine once I finally get some fruiting bodies? Thanks again for putting this together; it’s been a great resource for someone just getting into mushroom cultivation. Keep up the great work, and I look forward to seeing more guides from you in the future! Cheers, Zack