Mosquito control myths — what actually kills mosquitoes
Quick answer
Most backyard mosquito control is a myth. Bug zappers, citronella candles, ultrasonic gadgets, and repellent plants don't meaningfully reduce bites — some even make the yard worse. A few low-tech methods genuinely help, with honest limits. And one approach actually drops the biting-female population: a CO₂ + heat trap.
Mostly myths
These are the backyard staples that don't meaningfully cut bites — and a few that make your yard worse.
Bug zappers
Mosquitoes don't hunt UV. Zappers kill 99.9% beneficial bugs and almost zero mosquitoes.
Mostly a myth Why it doesn't work →Citronella candles
Open flame puts out CO₂ and heat — exactly what mosquitoes home in on.
Mostly a myth Why it doesn't work →Fogging & bug bombs
Wipes out bees, butterflies, dragonflies, and the spiders that eat mosquitoes.
Mostly a myth Why it doesn't work →Ultrasonic repellers
Apps, wristbands, plug-ins. Cochrane review of 10 trials: zero effect.
Mostly a myth Why it doesn't work →Bats & purple martins
Mosquitoes are under 1% of their diet. Martins eat dragonflies (which eat mosquitoes).
Mostly a myth Why it doesn't work →Repellent plants
Oil is locked inside the leaves. Sitting next to the plant does nothing.
Mostly a myth Why it doesn't work →Garlic, B-vitamins & dryer sheets
Every controlled trial: negative. Diet does not change how mosquitoes find you.
Mostly a myth Why it doesn't work →DEET-free 'natural' sprays
DEET has 65+ years of safety data. Natural oils evaporate in 20 minutes.
Mostly a myth Why it doesn't work →Ignoring small standing water
Aedes mosquitoes breed in a bottle cap. Gutters and saucers, not ponds.
Mostly a myth Why it doesn't work →"Mosquitoes only bite at dusk"
Aedes aegypti and albopictus are aggressive daytime biters. Sunscreen ≠ safety.
Mostly a myth Why it doesn't work →Works, with limits
These genuinely help — but each has an honest catch, so none is a complete answer on its own.
Dump standing water weekly
Gutters, saucers, toys, tarps. Costs nothing, does more than any spray.
Works with limits Where it helps →EPA-registered topical repellents
DEET, picaridin, IR3535, or oil of lemon eucalyptus on exposed skin.
Works with limits Where it helps →Bti larval dunks
A bacterium that only kills mosquito larvae. Safe for pets, fish, pollinators.
Works with limits Where it helps →The one that works
One method actually reduces the host-seeking females in your yard, backed by peer-reviewed field trials.
CO₂ + heat mosquito traps
A steady stream of bottled CO₂ and heat mimics a breathing mammal, so mosquitoes fly to the trap instead of you. Field trials show large reductions in landing rates — and pollinators, which don't host-seek for CO₂, are left alone.
See the science →