Why Is the Humidity so High in My Grow Room

Pro230 Grow Room Dehumidifier with Remote Control

High humidity in a grow room is typically caused by a combination of environmental factors, plant activity, and equipment setup.

Common Reasons for High Humidity in Grow Room

1. Transpiration from Plants

Plants release moisture into the air through transpiration. As your plants grow larger and more numerous, they contribute more water vapor, increasing humidity.

2. Overwatering

Excess water in the soil or growing medium can evaporate, adding moisture to the air. Ensure you're watering appropriately for your plants’ needs.

3. Poor Ventilation

Inadequate airflow prevents moist air from being exchanged with fresh, drier air. A lack of exhaust or intake fans can trap humidity inside the grow room.

4. Insufficient Dehumidification

If your dehumidifier is undersized, malfunctioning, or improperly placed, it might not be able to handle the amount of moisture in the air.

5. High Ambient Humidity

If the air outside your grow room is already humid, it can raise the overall humidity inside. This is especially common in humid climates or during the rainy season.

6. Evaporation from Open Water Sources

Standing water from reservoirs, hydroponic systems, or spills can evaporate, adding to the humidity. Cover open water sources when possible.

7. Heat from Lights

Grow lights, especially high-intensity ones, can warm the air, increasing its capacity to hold moisture. When lights are off and the temperature drops, this moisture condenses, causing spikes in humidity.

8. Closed System Without Regulation

A sealed grow room without proper air exchange or humidity control can quickly become too humid due to transpiration and evaporation.

How to Fix High Humidity

Improve Ventilation:

Use exhaust and intake fans to cycle out humid air and bring in fresh air.

Add a Dehumidifier:

Ensure the grow room dehumidifier is properly sized for your room and placed optimally. PREAIR supplies the best dehumidifier for grow room. If you are a commercial grower and want to get rid of humidity problems, please contact us for information as soon as possible.