Greenhouse Humidity Control – Fall and Winter Tips
Fall is already here. The colder temperatures and shorter days have a huge impact on greenhouse climates, and how to control it. So we put together a few tips for greenhouse humidity control in the fall and winter.
When it’s cold outside – close the greenhouse!
Lower outdoor temperatures lead to higher outdoor relative humidity, making it difficult to rely on ventilation for humidity management. The best way to deal with humidity in this case, is with a dehumidifier. By closing your vents and screens during the colder and more humid parts of the day (night-time, cloudy, or rainy days), you isolate your facility from the outdoor conditions, letting DryGair work to keep greenhouse humidity down within target range.
Less heating, more energy savings
Closing the vents and screens, and using DryGair to control greenhouse humidity in the fall and winter, helps keep the heat inside. Meaning you can heat much less than when relying on ventilation for humidity control. Furthermore, the electrical energy used by each DryGair unit translates into heat energy, giving a slight temperature boost to further decrease your heating needs.
Use thermal screens
One of the biggest advantages of spreading thermal screens is preventing condensation drips. When it’s cold outside, even with low relative humidity inside, the cooler surfaces in your facility, such as the roof and metal structures, can reach the dew point – causing condensation to form on them. Spreading the screens creates a physical barrier between condensation drips and the plants, protecting them from getting wet. Keeping water off your plants drastically reduces the chances of humidity-related disease outbreaks.
On longer nights – increase dehumidifer operating hours
Greenhouse humidity naturally spikes during dusk and dawn. To prevent high indoor humidity, we recommend extending the DryGair operating hours to include not only the night, but early morning and late afternoon as well, when sunlight radiation is low. This provides an active dehumidification boost to the greenhouse climate, even if the vents are cracked, helping prevent humidity spikes during these critical transition hours.
More grow lights – higher humidity
Working with supplementary lighting to make up for shorter days? Keep an eye on humidity! Plant transpiration is a balance between a few factors – radiation, temperature, and humidity. The extra lighting adds both heat and radiation to the greenhouse, increasing plant transpiration. Make sure to compensate for the additional humidity with slightly longer DryGair operation hours.