No one wants to waste their hard earned cash on a scam. That's why we've sorted through all of the most commonly shared lies about preventing mosquitos into one post. Just because a trendy blog says it or someone shares it on Facebook, it doesn't make it true!
1. Planting Plants to Repel Mosquitos
This is arguably the most commonly shared lie. I've seen it time and time again. It's a great lie because everyone really wants it to be true. Unfortunately, there is zero evidence that mosquitos are repelled by these plants. The list varies, but it often includes smelly herbs such as Rosemary, Lemon Balm, and Lavender. If you want to grow these to use them as an herb or for tea, go right ahead! But they won't do anything to solve your mosquito issue.
This lie was born out of a series of exaggerations. The essential oils extracted from many of these plants DO repel mosquitos, for a few hours at best, and only at very high concentrations. The presence of the plant itself would be orders of magnitude less potent and thus completely ineffective.
That being said, if you were to replace a mosquito favorite, like English Ivy or a Japanese Aucuba, with one of these smelly herbs, it might make that part of your garden less appealing to mosquitos as a resting spot.
If you want to use plants to wage war on mosquitos, your best bet is to plant a wide variety of plants native to your county. Adding sources of water that are either moving or larvicided against mosquitos can help too. This is because all of these things are beneficial to the wide variety of mosquito predators and help encourage a more balanced ecosystem that isn't so dominated by a single invasive mosquito species, like the tiger mosquito.
There is also a genus of plants, utricularia (bladderworts), that literally eat mosquito larva. There are several species, and you should only plant what is native to your area. You'll need a pond in order to plant it, but to me, this plant deserves the credit so often given to plants that are nearly useless (against mosquitos).
2. Citronella Candles
You probably have one or have previously had one. So I probably don't need to tell you that it doesn't work, but the placebo effect is real, so maybe I do. If you need to read the study yourself, here it is, but the TLDR is that they don't repel mosquitos.
3. Wristbands
Wouldn't it be great if simply wearing a wristband prevented mosquitos? If that actually worked, why wouldn't you just string together wristbands to hold up the string lights in your back yard and banish mosquitos forever?
There has never been any evidence presented that mosquito repellent wristbands work, and the theory of how they might work also does not make any sense. A wristband does not typically emit particles into the air, which would sort of negate it's impact anywhere other than your wrist. Please refer to the same study already linked for the candles if you really insist on seeing evidence.
4. Patches
Ok, so this one is at least more plausible than a wristband. The idea is that you wear a patch and the patch delivers an active ingredient to your body. This active ingredient, typically Vitamin B1, is then "emitted" from your skin and repels mosquitos.
I can see how people fall for it. Mosquitos are attracted to some blood types more than others, though skin color and skin microbiome are more important factors. So I can see how someone might think you could somehow make yourself less attractive by adding something to your body that mosquitos don't like.
I'd even go so far as to say there is probably a chemical out there that would work in this format. Would you *want* to purposefully infuse that chemical into your body? Probably not. But the B1 patches have been thoroughly debunked by actual scientists.
5. Essential Oil Bug Sprays That Don't Contain Lemon Eucalyptus Oil
Of the many essential oils sold for repelling mosquitos, the EPA recommends just one, lemon eucalyptus oil. All of the others either don't actually repel mosquitos, require a very high concentration that is uncomfortable or unpleasant, or wear off so quickly that they aren't a viable solution. Thyme oil, clove oil, peppermint oil, garlic oil, etc. are just not as effective. While the best of these also rans achieved protection for less than 2 hours, lemon eucalyptus oil was comparable to DEET and delivered lasting protection for 4-6 hours.
6. Ultrasonic Devices
Something about the word ultrasonic just convinces people. It's like blockchain or AI, just add it to the name and it'll sell. The idea is that ultrasonic sound waves will repel mosquitos. Sort of similar to devices people use to prevent rabbits from eating their vegetables (do those even work? I'm honestly not sure).
However, I am sure that ultrasonic devices do NOT work on mosquitos. This is because actual scientists conducted a study and showed that ultrasonic devices do not repel mosquitos. I mean seriously, how do companies still sell their product after being so thoroughly debunked? I honestly don't get it. The ultrasonic device actually attracted more mosquitos than the control.
7. Incense
It took us a bit, but we've finally found one that is in a bit of a gray zone. There *is* some evidence that incense products sold to repel mosquitos have a modest effect. But, and it's a big but, the particulate matter issue is too concerning to ignore. We had to tell you about this one.
According to this study, "mosquito coils" sold to repel mosquitos released as much PM2.5 mass as burning 75-137 cigarettes would. It also released as much formaldehyde as burning 51 cigarettes. It does make sense -- you're burning something that is designed to release particles into the air that repel mosquitos. It shouldn't be surprising that the air would then be harmful to humans too. We share roughly 60% of our DNA with insects.
8. Bug Zappers
This one is actually tragic. Not only are bug zappers not effective against mosquitos, but they are *very* harmful to beneficial insects, especially moths. You don't have to look far to understand why.
These bug zappers claim that the light source(sometimes a UV light source to be extra fancy) attracts mosquitos. Sadly for this absurd claim, mosquitos are not attracted to light. They are in fact attracted to the opposite, complete darkness. What's attracted to light? Go outside at night and look at your front porch lights. Mostly moths. Some craneflies. See any mosquitos? Very very unlikely. Now picture that your porch light is the zapper and everything attracted to it gets zapped. That's what a bug zapper will do for you.
And if a rational argument isn't enough for you, don't take our word for it, because actual scientists tested one out and proved exactly what you just read. In a single night, a bug zapper killed about 10,000 insects and only 8 of them were mosquitos.
9. Bats
First of all, despite the bad rap they got for their role in COVID-19, bats are wonderful and a lovely part of the ecosystem. Are they a mosquito predator? Absolutely. Will they eliminate your backyard mosquito issue if you put up a bat box? Absolutely not.
First, let's talk about time of day. Bats are active at night. Tiger mosquitos, which are currently 99% of the problem in our service area, are active during the day. How exactly are bats going to significantly reduce the population of an insect that is fast asleep while bats are catching insects out of the air? If the night-biting northern house mosquito were the only issue, maybe there's an argument.
Secondly, however, bats are not very particular. It's not as if they are hunting down mosquitos specifically. If you want them to completely eliminate (night biting) mosquitos, they'd likely have to also eliminate all of the other insects active at night. If they somehow did that, they'd move on and leave the area, because they'd no longer have a source of food!
If you want to support bats by installing a bat box, that is fantastic and we endorse it. Bats are an important part of the ecosystem and they are in many cases declining. However, don't install a bat box thinking it will prevent mosquito bites from tiger mosquitos while you're gardening mid-afternoon.
10. Purple Martins
Again, let us first say, purple martins are awesome and we love them. If you put a purple martin in an enclosed area filled with mosquitos, it will eat them, as it is opportunistic. This is where this myth came from, and is why you'll see claims like "purple martins can eat 2000 mosquitos per day". However, in actuality, the diet of a purple martin contains very few mosquitos, across many studies.
This again makes sense if you understand the biology of both purple martins and mosquitos. Purple martins hunt "on the wing" swooping their prey out of the air. But, they typically fly at least 15 feet above the ground, whereas mosquitos hug the ground closely. It's no wonder that mosquitos make up such a small part of the purple martin diet when they barely come into contact with each other.