Does Lemongrass Really Keep Your Rain Barrel Mosquito-Free?

If you're a fairly serious gardener and you live in a part of the world that gets plenty of rain, you might DIY your own rain barrel or purchase one. Rain barrels collect water for a couple of reasons; they can prevent run-off from flooding the street or seeping into waterways and polluting them. Or you might use what you collect to water your ornamental plants. But any vessel or surface with standing water is notoriously attractive to mosquitoes, those annoying bloodsuckers and bringers of disease, and you'll want to take measures to get rid of them. There's a hack making the rounds on social media that suggests cutting up bits of lemongrass into your rain barrel to repel mosquitoes. Well, we know citronella oil is certainly a useful and popular mosquito repellant. But while this hack sounds intriguing, lemongrass alone doesn't have enough concentrated citronella firepower to be a reliable fix.

Lemongrass is special it contains citronella. Anyone who eats outdoors on the patio will tell you that their citronella candles are an indispensable defense against mosquitoes. Citronella is a mosquito-repellant ingredient in both commercial sprays and homemade remedies DIYers make with its essential oil. The idea of letting lemongrass plants marinate in a vat of water to perfume the air with a yummy scent sounds delightful to us, but it's unlikely to be potent enough to repel mosquitoes.

Let's first ask if and how citronella works. Though there aren't yet scientific studies to verify whether it works in rain barrels, mosquitoes dislike the scent, and it's thought that citronella interferes with the insects' ability to sniff out prey. The citronella oil might disguise or mask the scents mosquitoes like. Citronella works to keep mosquitoes away in commercial bug sprays — but only when the concentration is high enough, so its effectiveness can vary. It's not an insecticide, but it will redirect them away from wherever you spray the oil.

Oil is the keyword here. One of the reasons you may have only moderate, if any, success with this hack is that compared to a preparation made from oil, which contains a higher dose of citronella, chopping up a few pieces of lemongrass into a barrel of water makes a fragrant outdoor soup, but contains only a fraction of what's needed for a deterrent. Also, algae and bacteria can become a problem in rain barrels. Leaving lemongrass stalks in the water means they'll eventually decompose and potentially become a bacteria snack. Instead, to wage an effective anti-mosquito campaign, switch to a dark-colored barrel, make sure it has a cover, and install mosquito mesh covering under the lid as extra insurance.