Properly ventilating a greenhouse is imperative to the health and well-being of the garden. The concept of utilizing a greenhouse to modify and control the environment is in vain if ventilation and indoor air quality are overlooked. Ventilation is about a lot more than just keeping the greenhouse from overheating.
Plants require co2 for photosynthesis and without supplementation or fresh air, the available co2 within a closed system can be quickly depleted. Stale stagnant air combined with humid environments typically found in greenhouses create the perfect storm for fungus and mold spores to grow and flourish. Circulation fans (HAF fans) are critical for keeping the air moving and temperatures within the greenhouse consistent. In a natural outdoor environment, the wind is continually strengthening plant stems and stalks. Inside this must be artificially created by having a gentle breeze moving the plants around. Pests also find moving air environments less favorable and will not proliferate as quickly.
We offer both mechanical forced air ventilation and passive ventilation either manually operated or automatically via special wax openers activated by temperature. When properly setup with exhaust fans, intake shutters, HAF fans, timers, and controllers the environmental conditions within the greenhouse become fully automated allowing you to go away for extended periods of time and still maintain optimal conditions without daily maintenance. In the intense summer, sun greenhouses can overheat very quickly subsequently frying your plants in a single day. If you would like to further control or perfect the environment we offer dehumidifiers, evaporative coolers, co2 burners, and all the required controls to increase plant health and growth rates. For those in a cold climate or a desire to garden year round even in a warmer climate adding a heater to your greenhouse will be a necessity. In both warmer and colder climates, a heater will help maintain ideal conditions without the temperature swings. Colder climates will require more frequent use of the heater particularly when nighttime temperatures drop low despite high summer daytime temperatures. Heating the greenhouse will enable an earlier start in the spring and a season extension in the fall.
Greenhouses can cool down when the sun drops just as quickly as they heat up as the sun rises. A thermostatically controlled heater will help alleviate large temperature fluctuations keeping your plants healthy. In northern climates, the common misconception about warm weather crops not finishing is that the growing season is too short but the cold nighttime temps are equally at fault. When temps drop below approximately 50 degrees tomatoes and peppers, for example, are going dormant resulting in dramatically stalled growth rates.