Keeping the greenhouse cool in the dog days of summer can be a challenge for the new greenhouse gardener. Frequent monitoring is required to ensure the safety and health of your plants. There are several common methods for cooling a greenhouse.

Cool Fog Systems or Evaporative Coolers

One way to cool your greenhouse is to install a cool fog system. A cool fog system forces miniature droplets of water into the air of the greenhouse. This mist does not saturate the foliage of the plants because the droplets are too small and evaporate in the air. This process of condensation creates a lowered air temperature in the greenhouse. Another helpful tool to keep your greenhouse cool is an evaporative cooler.

Keeping the Greenhouse Cool in Summer: Ventilation

One of the simplest ways of cooling the greenhouse is to use a system of vents and exhaust fans. Vents placed near the roof of the greenhouse allow hot air to escape the greenhouse as it rises. This creates air movement in the greenhouse that pulls fresh air from outside the greenhouse inside through air vents open near the bottom of the greenhouse walls. Ventilation shafts placed in this manner create a constant flow of fresh air from the outside of the greenhouse. Usually, the ventilation openings are louvered to allow the gardener to open and close the vents to control the temperature inside the greenhouse.

Keeping the Greenhouse Cool: Shading

Another simple way to help control the air temperature inside the greenhouse during summer is shading. A retractable shading system is by far the most convenient. Blocking the sun’s rays from entering the greenhouse during peak temperatures can save the gardener money in active cooling costs.

Keeping the Greenhouse Cool in the Dog Days of Summer: Circulation Fans

Fans are a staple in nearly every greenhouse. Fans are used to help with pollination, circulate air, and help control the air temperature of the greenhouse. Ventilation fans should be placed no farther apart than 25 feet. If a greenhouse measures 25 feet in length or more, two fans are needed and should be spaced evenly in the greenhouse to provide proper ventilation.

Keeping the Greenhouse Cool in the Dog Days of Summer: Fan and Pad Systems

The fan and pad method of greenhouse cooling involves using a special pad placed at one end of the greenhouse. This special cellulose pads are fed a constant supply of water. Strategically placed fans draw air in through the pads, creating an evaporating effect as the water cools. This is the most common type of cooling system used in commercial greenhouses.

Keeping the greenhouse cool in the dog days of summer helps plants continue growing for optimal crop yields. Today’s greenhouse gardener has many choices when selecting a method of greenhouse cooling.