Now that Spring is giving way to Summer….we find the heat build-up in a greenhouse can prove stressful to your plants…sometimes, even fatal.To counter the extreme heat build-up in a greenhouse, you’ll need to exchange the volume of air at least once per minute. Beyond ridge vents and sidewall vents which have their limitation to how much air can be moved….the next step in combating the heat is a mechanical ventilation system – consisting of a shutter-mounted exhaust fan placed high in one gable end wall….and a motorized air-inlet shutter typically mounted on the opposite gable end wall at or below bench top level.
If your plant collection is made up of orchids and other environmentally sensitive plants; you may want to consider the addition of an evaporative cooling system.
An evaporative cooling system can effective drop the temperature up to 15 + degrees below that of the outside ambient air temperature. The level of humidity in your particular area will have a bearing on the performance of an evaporative cooling system….the higher the humidity, the less effective the system.
The next item at our disposal in the battle to combat the heat is the humble Shade Cloth tarpaulin. Coming in a variety of shade densities, traditionally, black shade cloth is the least expensive…and can actually result in heat gain.
A very effective alternate to the black shade is ‘Aluminet Shade Cloth ’….a heat-reflective shade cloth is made up of thin aluminum strips woven together in a lock-stitch weave that does not come unraveled….with temperatures 10 – 15 degrees less than the outside air.
These simple measures can make a tremendous difference in allowing your to control the summer heat so you can utilize your greenhouse during the warmer months of the year.
Let us know if need any help in planning how to design an effective ventilation, evaporative cooling or shade cloth system for your greenhouse.
Happy Growing ~ from the folks at Gothic Arch Greenhouses Inc