Greenhouse Humidifier — Humidity and VPD Control for Greenhouses, Mushroom Farms, and Indoor Grow Rooms

There is no single answer — it depends on the crop, growth stage, and temperature. For most vegetable crops during active growth, 60–75% RH (VPD 0.8–1.2 kPa) is optimal. During propagation, 80–90% RH (VPD 0.2–0.5 kPa) prevents desiccation of unrooted cuttings. During flowering, 55–65% RH reduces fungal disease pressure. Use VPD as the control parameter rather than RH alone, because RH changes with temperature while VPD reflects actual transpiration demand.

During incubation (mycelium colonization), 70–80% RH. During pinning initiation, 95–100% RH to trigger primordia formation. During fruiting, 85–95% RH for full cap development. Below 80% during fruiting, pins abort and caps crack. Species-specific ranges vary — tender species like lion's mane require the upper end (90–95%), while tougher species like reishi tolerate the lower end (80–90%). Maintain a 10% RH differential (e.g., max 95%, min 85%) to allow slight surface drying that helps prevent bacterial blotch.

No, under normal operation. The SHISHUO UH-DS produces 0.5–5 micron droplets that evaporate in the air before settling on surfaces. Maintain 2+ meters of clearance between the mist outlet and the nearest crop surface. Do not point the outlet directly at mushroom fruiting bodies or plant canopy — aim upward to allow thorough air mixing. The goal is to raise ambient humidity, not to mist the crop directly.

Yes, the UH-DS hardware is the same. The difference is the set-point. Plants typically need 55–80% RH depending on stage; mushrooms need 85–95% during fruiting. If you run separate rooms for each, deploy a dedicated unit in each room with its own RH target. The automatic control adjusts output to maintain whatever set-point you configure.

If RH in your flower room is consistently above 55–60%, you need a dehumidifier, not a humidifier. During late flowering with dense canopy, plant transpiration often pushes RH above safe levels, creating Botrytis risk. A SHISHUO GDH commercial dehumidifier removes excess moisture and brings RH back into the safe range for flowering. The humidifier is for earlier growth stages or dry-climate conditions where RH drops below the target.

Mushroom rooms require high humidity (85–95% RH) while exchanging air 1–3 times per hour for CO₂ management. Each air exchange removes moisture. A 50 m² room with 3 m ceilings (150 m³ volume) exchanging air twice per hour replaces 300 m³ of humidified air with outside air every hour. Depending on outdoor RH, this can require 3–6 kg/h of moisture replacement. The UH-DS-06E (6 kg/h) is a common starting point for this size room. For larger rooms or higher air exchange rates, step up or deploy multiple units.

Yes, partially. Ultrasonic humidification produces an evaporative cooling effect as the fine droplets absorb heat from the air during evaporation. This can reduce air temperature by 2–6°C depending on conditions. It is a supplemental cooling benefit, not a replacement for dedicated greenhouse cooling systems (shade cloth, ventilation, evaporative pad-and-fan). But in dry climates where both humidity and temperature are challenges, the cooling effect is a meaningful bonus.

Yes. We support OEM branding and ODM modifications including capacity adjustments, voltage adaptation, custom housing for integration into greenhouse climate control systems, and pipeline distribution configurations for multi-zone coverage. Contact our team with your requirements.