We all know how pesky mosquitoes are and that they can be carriers of Zika, Dengue, Chikungunya and other diseases, making these great reasons to have mosquito repellents. For the garden, one common choice is citronella, an essential oil that comes from a plant (Cymbopogon nardus), which is a member of the geranium family.
If you’re considering citronella plants for your yard as a way to repel mosquitoes, entomologist Roberto M. Pereira, PhD, an insect researcher with the University of Florida says “if you just have the plants around, that’s not enough to keep mosquitoes away from your yard unless you have a lot,” noting that the plant’s repellent properties are not enough to sway mosquitoes.
If on the other hand, you’re thinking of arming your yard with citronella oil to burn, you may be surprised to learn that that too, is ineffective. According to the American Mosquito Control Association, there is no scientific evidence to show that burning citronella candles repels mosquitoes.
A 2017 study published in the Journal of Insect Science also came to the same conclusion, that burning citronella candles is an ineffective way to be rid of mosquitoes. As a matter of fact, their studies, which were done on the Aedes aegypti mosquito, the principal vector of these diseases, found that a majority of commercial anti-mosquito products proved ineffective.
So what does work at keeping mosquitoes away when you’re outside? The most simple solution is an outdoor fan. If your yard is free of standing water, which is known to be a mosquito breeding ground, and you do not want to go the spray-on chemical route, an outdoor fan is ideal. Make sure it is aimed low, however, since mosquitoes tend to fly close to the ground.