Quick answer
You can mix a homemade mosquito spray, but be realistic about what it does. The popular mouthwash (Listerine) sprays don't work — they're too diluted and evaporate too fast. Dish soap in water can kill mosquito larvae by breaking the water's surface tension, but it won't repel adults. The one DIY ingredient with real backing is oil of lemon eucalyptus, a repellent the CDC recognizes — though homemade mixes aren't tested for the right concentration. For your skin, an EPA-registered repellent is the reliable choice; for your yard, removing standing water and running a trap does more than any spray.
Why people make their own mosquito spray
Search "homemade mosquito spray" and you'll find hundreds of recipes promising a cheap, quick fix with ingredients already in your kitchen. Some are rooted in real science; most are wishful thinking that's been copied from blog to blog for years. Before you mix anything, it helps to know which recipes have evidence behind them and which just smell like they're working. Here's an honest breakdown.
Do DIY mosquito sprays actually work?
| DIY recipe / ingredient | What people claim | What the evidence shows |
|---|---|---|
| Mouthwash (Listerine) + vinegar | Kills/repels mosquitoes | ❌ Myth. Listerine is under ~1% essential oils and evaporates fast; fact-checkers and the CDC's concentration guidance say it won't protect you. |
| Dish soap in water | Kills mosquitoes | ✅ Can kill larvae by breaking surface tension. ❌ Doesn't repel adults, and it harms aquatic life — keep it out of ponds. |
| Oil of lemon eucalyptus (OLE) | Plant-based repellent | ⚠️ A genuinely recognized repellent (CDC) — but homemade versions aren't tested for the concentration or duration that store-bought, registered products are. |
| Lavender / lemon / vanilla oils | Repels mosquitoes | Some short-lived repellency in lab settings; don't expect hours of yard-wide protection. |
| Garlic, cayenne, onion | Repels or kills | Anecdotal; little solid evidence. |
| Beer + mouthwash + Epsom salt | Yard spray | No real evidence it works. |
Why the mouthwash spray myth won't die
The Listerine spray is the most-shared mosquito hack online — and one of the least effective. Mouthwash contains a small amount of eucalyptol, which is found in some real repellents, but at less than ~1% concentration it's far below what's needed to deter a mosquito, and it evaporates within minutes. Independent fact-checks have repeatedly rated the "spray Listerine to keep mosquitoes away" claim as false. If a DIY mix feels like it's "working," it's usually the brief masking smell — not lasting protection. (PolitiFact)
If you still want to make one: the honest recipes
Two DIY approaches have at least some real basis. Neither replaces a registered product, but here's how to do them properly:
- Essential-oil skin spray (short-term). Mix a few drops of oil of lemon eucalyptus or another essential oil into a carrier (like witch hazel or a light oil) before spraying — never apply undiluted oils to skin. Expect close-range, short-lived repellency, and reapply often. Don't use OLE products on children under three.
- Soapy-water larvae treatment. A drop of dish soap in a container of standing water breaks the surface tension larvae rely on to breathe. Use it only on water you're about to dump — never in ponds, fountains or anything that drains to natural water, since soap harms fish and other aquatic life.
The one DIY idea with real science: surface tension
That soapy-water trick points to the one principle worth building on. A surfactant breaking the water's surface so mosquitoes can't escape is exactly how the trap in Mosquito TNT 2.0 works on the adults it draws in, alongside a dual-stage reaction that releases carbon dioxide for up to 30 days — the cue mosquitoes use to find a host. You just add warm water to a jar of simple pantry-style ingredients (yeast, sugar, baking soda, citric acid and a surfactant). No electricity, no propane, refillable, DEET-free*, and safe to use around kids and pets when used as directed. It's the reliable version of the soapy-water idea — built to last a month instead of a single bowl. *Not a safety claim.
For more yard-level tactics, see our guides on how to mosquito-proof your yard, getting rid of mosquitoes in your room at night, and the best mosquito traps for the yard.
Frequently asked questions
Does mouthwash spray actually repel mosquitoes?
No. Mouthwash like Listerine contains under ~1% essential oils and evaporates within minutes — well below the concentration the CDC says a repellent needs. Fact-checkers have rated the mouthwash-spray claim false.
Does dish soap kill mosquitoes?
It can kill larvae in standing water by breaking the surface tension they rely on to breathe, but it doesn't repel adult mosquitoes, and it shouldn't go into ponds or natural water because it harms other aquatic life.
What's the most effective homemade mosquito repellent ingredient?
Oil of lemon eucalyptus (OLE) is the standout — it's recognized by the CDC as an effective repellent. The catch: homemade blends aren't tested for the right concentration or how long they last, so results vary.
Do essential-oil sprays (lavender, eucalyptus) work?
They can give short-term, close-range repellency, but the effect fades fast and won't blanket a yard. Use them as a light extra, not your main line of defense.
What actually works better than a DIY spray?
For skin, an EPA-registered repellent is the dependable choice. For your space, remove standing water (the breeding source), screen windows and doors, run a fan, and use a CO2 bait-and-trap like Mosquito TNT 2.0 outdoors.
Mosquito TNT is not currently available in New Mexico and Tennessee.