Garden experts reveal how to cool down a greenhouse

Green-fingered Brits are being offered tips on how to keep greenhouses cool during summer.

Experts at GardeningExpress.co.uk have provided their advice on how to prevent an overheated greenhouse from damaging plants as the temperatures begin to rise.

Greenhouses can easily overheat during the hot summer months, leading to wilting, stunted growth and plant death.

Proper temperature management and ventilation can ensure optimal growth and help plants absorb nutrients.

Gardeners are urged to open the greenhouse doors and vents on sunny days and leave them open overnight if the temperature stays high.

To keep the greenhouse cool, it’s worth considering installing fans to improve air circulation or evaporative cooling systems which use the heat in the air to evaporate water.

To protect plants from the bright sun rays, it’s recommended to use a shade cloth which provides UV protection and helps keep the greenhouse cool, while still allowing sufficient light for plant growth.

Chris Bonnett from GardeningExpress.co.uk said: “Although greenhouse gardening is a great solution for year-round planting, it can bring some challenges during hot summer days.

“To protect plants from the heat, we’re urging gardeners to be mindful of temperatures and implement cooling strategies to prevent overheating.

“The first step is to ensure the greenhouse is properly ventilated which can be done naturally by leaving the doors and vents open on sunny days.

“Other solutions include installing shade cloths, fans, misting systems or reflective insulation.”

Here are GardeningExpress.co.uk‘s tips and advice on how to keep the greenhouse cool during summer:

1. Provide natural ventilation

For natural ventilation in a greenhouse, it’s essential to open the doors, windows, and vents on hot summer days. This allows hot air to escape while enabling cooler air to circulate throughout the greenhouse, creating a suitable environment for plant growth. Try to do this for a few hours in the morning or the evening when the temperature is cooler. 

2. Use shade cloths 

Shade cloths prevent sun damage by providing protection from intense UV rays while still allowing in enough light for plants to thrive. They come in different densities so gardeners can choose the level of shading they need.

3. Use fans 

Place fans in your greenhouse to improve air circulation. They promote constant air movement which prevents the buildup of excessive heat. Exhaust fans should be placed high up to remove hot air and circulating fans should be at plant level to enhance airflow.

4. Install evaporative cooling systems

An evaporative cooling system draws the warm air through water-saturated pads, where the evaporation of water absorbs heat and cools the air, which is then circulated to reduce the overall temperature. This method is both eco-friendly and cost-effective, making it a great solution with minimal energy costs.

5. Add reflective insulation

Reflective insulation reflects heat away from the greenhouse, reducing the amount of heat that enters and helping maintain a stable, cooler temperature.