Under cover
Ventilation
A closed greenhouse can climb well above 30C on a bright day, even when the air outside feels cool. Open vents and doors early, take care when working inside, drink water, and step out if you start to feel hot, dizzy or unwell.
- Where to get help
- NHS 111 or seek medical advice
Open vents, doors and louvres on warm days.
Best for
All covered growing
Notes
Heat builds fast under glass even on a cool sunny day.