Controlling humidity at night is crucial in greenhouses and grow rooms. Most plants transpire water at night and day, resulting in high relative humidity.

This increases the risk of disease outbreaks and mold formation in nearly any crop, including vegetables, flowers, and cannabis. This issue can occur in any regulated growth setting, from greenhouses to indoor grow rooms.

Plants do not photosynthesize at night since there is no light. As a result, many people believe they "shut down," and their physiological functions stop. However, this is not the case.

Plants continue to respire or breathe during the night. This implies they open their stomate and emit CO2, causing water to evaporate.

Even when there is no sunlight, nighttime respiration is crucial for plant growth.

Nighttime transpiration issues emerge in closed growing situations because humidity becomes trapped inside the area.

This means that relative humidity can quickly approach the dew point and reach 100% saturation. Once this occurs, water will begin to condense on cooler surfaces, such as greenhouse coverings, metal railings, or even the plants themselves.

High relative humidity, or low VPD, is inefficient and hinders plant development. More importantly, high humidity can promote the growth of diseases and molds such as powdery mildew, Alternaria, and botrytis.

Heating and ventilation are effective at reducing nighttime greenhouse humidity.

Plants do not only transpire at night. During the day, they breathe and expel water vapor. The difference is that producers can open their greenhouses or use ventilators to discharge the damp air during the day. This is only possible if the environmental conditions are favorable, which means the humidity is low, the temperatures are moderate, and it is not raining.

Heating is a method used by farmers to minimize humidity overnight. Heating lowers relative humidity by increasing the ability of the air to store water vapor. This aids in the prevention of condensation but is not always 100% effective.

The issue with heating is that it does not physically remove water vapor from the developing environment. As a result, after the heating is switched off and the temperatures decrease, the humidity will rise dramatically. Furthermore, heating is not always possible. On warm nights, heating might cause the space to become overly hot. This is why AutoVent 's controllers will open the vents to leave humid air escape. This controls your greenhouse humidity effectively.

Heating a greenhouse uses a lot of energy, whether you use electric or gas heaters, which means increased costs. This is why it's very hard to do manually. AutoVent environmental controllers make it easy and economical to exactly match your setpoint.