Arty Schronce, Director of Public Affairs for the Georgia Department of Agriculture, was recently asked if painting a porch blue would help control insects.
I agree with his response:
“This is a common belief, but there is no scientific evidence to suggest it does. Insects are generally attracted to light-colored surfaces more than dark surfaces. So, they’d probably be more attracted to light blue than dark blue, but you could say that about most colors or plain white. The color blue likely has nothing to do with it. And houseflies are unlikely to choose to stay on the ceiling regardless of its color when there are food or sweet drinks being consumed below or inside the house. Some posit that spiders and wasps will think the ceiling is open sky and not build webs or nests there, but, again, there is no scientific evidence for this.
“Painting porch ceilings light blue has been a longstanding custom for some people in parts of the South. Some suggest it started from an African belief that blue helps keep evil spirits away. In the days before air-conditioning, the porch was a busy and welcome part of the house where people went to escape the heat and stuffiness of the indoors. There were even “sleeping porches” with beds where residents could spend hot summer nights and take advantage of evening breezes. A blue ceiling may have had had a psychological cooling effect on people seeking relief from sweltering temperatures.
“Whatever the reason – insects, haints, cooling effect, personal taste, or just tradition – blue ceilings for porches are as popular as ever and are starting to appear in areas outside the South.”