Do Citronella Candles Work?
Citronella candles are a summer staple, especially if you live in mosquito country. But when you light up those dollar store tiki torches do you ever wonder, “do citronella candles actually work?” – I’ve done the research so you don’t have to.
Do citronella candles work? Not exactly. While they can be helpful to repel mosquitos in the direct vicinity of the candle, they have very little effect on keeping them away from your yard or even your guests.
So now you’re probably wondering: have we been fed a lie? Are all those citronella candle companies scamming us by advertising their products as mosquito protection?
The truth is actually a little more complicated than whether or not citronella candles do or don’t work.
What is a Citronella Candle?
Before we get into it, a citronella candle is a type of candle that includes citronella oil made from Cymbopogon, often called lemongrass or citronella grass. Most of these candles contain 3% or 5% citronella oil when advertised as a mosquito repellent.
Most of the time, citronella candles come in two varieties: a standard candle that can be burned outdoors, and “tiki torches” that can be pushed into the ground. The latter is often used for parties and events to ward off mosquitoes over a larger area.
Citronella candles smell citrusy and sweet.
Are Citronella Candles Safe?
Generally speaking, citronella candles are regarded as safe especially when burned outdoors in well ventilated areas. Animals, especially cats, can be sensitive to the smell, though.
Citronella oil may contain a chemical called methyleugenol, though, which is considered carcinogenic. Citronella candles only have small quantities of citronella oil, and are often not being inhaled or against the skin, so the risk is generally considered minimal.
Health Canada recommends against using citronella oil based bug repellants that are exposed directly to the skin.
Citronella Oil as Mosquito Repellent
On its own, citronella oil has been proven to repel mosquitoes, so there is some science there to back up its initial use. Check out this study on natural mosquito repellents.
However, there’s a few problems with this
First of all, the data isn’t conclusive and there’s plenty of variables that affect how effective citronella oil is at repelling mosquitoes from humans. So even if on its own the oil works, it doesn’t necessarily have a great application yet.
Second, related to the first point, the poison is in the dose, so to speak. Citronella candles only have a small amount of oil in them, and not enough to effectively repel mosquitoes. Studies were conducted with pure citronella oils.
Third, citronella isn’t the only thing that repels mosquitoes well. For example, the study linked above found that L. sinense protected better than citronella, and other oils like pine and peppermint were comparable.
So basically yes, citronella oil repels mosquitoes, but it’s not the same as a citronella candle.
Science Says Citronella Candles Don’t Really Work
One of the most convincing studies is one that was done to compare a variety of mosquito prevention tactics, including wearable devices and citronella candles.
They used a wind tunnel to help eliminate variables, which makes it even more credible than other studies. If you don’t want to read the whole study, the conclusion when it came to the citronella candle is that it didn’t have any repellent effect whatsoever.
In fact, they actually had more interactions while burning a citronella candle between the human bait and mosquitoes than with the human alone. Although the results weren’t statistically significant to say it had a negative effect, it’s definitely ironic.
OK But Really, Do Citronella Candles Work?
If you’re still reluctant to dismiss citronella candles entirely, I don’t blame you. Anyone who’s used them outside has felt like they at least had some sort of impact, even if it was small. Have you been feeling a placebo effect, or do citronella candles work?
This is where that “sort of” answer comes in. While they’re definitely not 100% effective at preventing mosquito bites or keeping you safe from West Nile and other viruses, studies have shown that citronella candles do reduce the amount of bites.
One meta analysis on citronella candles, for example, found that they reduced bites by up to 42% compared to being outside without any protection.
Of course, there are limitations to this, including how far away you can be from the candle before it stops having any effect, but it still proves that they at least can help a little.
Another thing to consider is that most studies used mosquito bites as their measurement of efficacy. While it’s fair to assume that less bites mean less mosquitoes, if you’re looking to reduce the amount of bugs buzzing around, and not just prevent bites, you may find citronella candles help with that.
Alternatives to Citronella Candles
It’s clear that citronella candles aren’t going to stop you from getting bitten by mosquitoes. If disease is a concern, a combination of protection and DEET is still the most effective choice.
Besides bug spray, there are other ways to scare off mosquitoes from your yard that you can use instead of or alongside citronella candles.
Believe it or not, fans are a great natural mosquito repellent. Adding a relatively strong fan to your patio or deck during the summer can help keep you cool and keep bugs from bothering you. No chemicals required.
They’re not 100% effective, but bug lights are handy at keeping all kinds of flying insects away from you outdoors. Look specifically for one that uses octenol, a pheromone that will attract mosquitoes. Mount it close enough to be effective.
There are a few varieties of these, but sadly their efficacy varies. Natural ones may not work better than citronella candles, and other varieties could have negative health effects. Some brands, like OFF, have better reviews than others.
Do Citronella Candles Work? – Final Thoughts
It’s evident that citronella candles aren’t even 50% effective at preventing mosquito bites, which means they won’t save you from disease or bites. That being said, they can help a little bit in conjunction with other preventative measures, are largely considered safe to use, and smell nice.
In short, citronella candles do not work as well as advertised, but they can still be an addition to your backyard this year – just as long as you’re not only relying on them to keep you bite-free.