Insects that have very little ability to regulate their internal body temperature are termed ectotherms. For these insects, when it gets below the temperature at which they can generate enough energy to fly, they will become inactive.
Wasps can technically fly for a short period at temperatures below 50-53°F, but they will become lethargic and fall to the ground quickly. It is safe to say that below 53°F wasps become lethargic and unable to fly.
What Is The Temperature At Which Wasps Cannot Fly?
As it gets colder in fall, trees and plants reduce their flowering. The amount of sugar available for the wasps’ declines – at the same point we are dealing with the wasp nest at its largest size as it has multiplied up over the summer.