How do you get rid of mosquitoes in your backyard?
Short answer: Remove breeding sites first. Once a week, empty, scrub, cover, or throw out anything that holds water, as the CDC advises. Treat water you can't drain, like rain barrels or ponds, with a Bti larvicide such as mosquito dunks. Keep screens tight, and use an EPA-registered repellent such as DEET, picaridin, IR3535, or oil of lemon eucalyptus.
Why is standing water the main problem?
Mosquitoes lay eggs in water, where the larvae develop. UC IPM says the most effective approach targets the larvae. Spraying adults gives only a temporary reduction.
How often should I dump standing water?
At least once a week. The CDC says to “empty and scrub, turn over, cover, or throw out items that hold water” weekly. The EPA gives the same weekly interval for birdbaths, fountains, and wading pools.
Common sources to check:
| Item | What to do |
|---|---|
| Buckets, toys, flowerpot saucers | Empty and scrub weekly, or turn over |
| Birdbaths, fountains, wading pools | Change the water at least weekly |
| Old tires | Remove, or empty the water |
| Rain gutters and downspouts | Clear clogs so water drains |
| Rain barrels | Cover openings with window screen |
| Swimming pools | Keep treated and circulating |
| Holes or low spots that hold water | Drain, or fill with soil |
Sources: CDC, EPA, and UC IPM. Our gutter cleaning guide covers doing that job safely.
What about water I can’t drain?
Use a larvicide made with Bti (Bacillus thuringiensis israelensis). Per the CDC, Bti is a soil bacterium that is toxic to mosquito larvae, blackflies, and fungus gnats. It has been used for mosquito control for more than 30 years.
Key points from the CDC and UC IPM:
- Homeowners can place Bti dunks or bits by hand in small bodies of water.
- Mosquito dunks are time-release rings that float on the water. UC IPM says they last about 30 days.
- Bti kills larvae. It does not control biting adult mosquitoes (CDC) or pupae (UC IPM).
- The CDC says larvicides used according to the label “do not harm people, pets, or the environment.”
UC IPM also lists methoprene and spinosad as larvicides for standing water. Mosquitofish can help in isolated, man-made water features. Do not release them into streams, ponds, or lakes. UC IPM notes that doing so is illegal in California, and many states restrict it.
Always follow the product label for dose and reapplication.
How do I keep mosquitoes out of the house?
- Install window and door screens and repair holes (CDC).
- Seal gaps around walls, doors, and windows (EPA).
- Use air conditioning if you have it (CDC).
- Cover baby carriers, strollers, and beds with mosquito netting.
Which mosquito repellents work?
The CDC recommends EPA-registered repellents with one of these active ingredients:
| Active ingredient | Note from CDC |
|---|---|
| DEET | EPA-registered |
| Picaridin | EPA-registered |
| IR3535 | EPA-registered |
| Oil of lemon eucalyptus (OLE) | Not for children under 3 |
| Para-menthane-diol (PMD) | Not for children under 3 |
| 2-undecanone | EPA-registered |
Look for an EPA registration number on the label and reapply as directed. The CDC says it does not know how well non-registered repellents work, including some natural ones. UC IPM says repellent protection typically lasts 4 hours or less, depending on heat, humidity, wind, and sweat, and products under 10% active ingredient may last only 1 to 2 hours.
For clothing, the CDC suggests loose long sleeves and pants. You can treat clothing and gear with permethrin, which lasts through multiple washings. Never put permethrin directly on skin. If you use sunscreen, apply it before repellent.
Do bug zappers and ultrasonic devices work?
Not well, according to UC IPM.
- Bug zappers: UC IPM calls them counterproductive because they kill insects that prey on mosquitoes.
- Ultrasonic devices: UC IPM lists them as ineffective.
- Citronella candles and mosquito coils: UC IPM says these work best when air is still. They are for outdoor use only.
- Continuous-release insecticide systems: UC IPM does not recommend them.
Yard sprays and foggers give only a short-term drop in adult mosquitoes. The EPA says larvicide and adulticide programs are mainly for professionals. You can support local programs by pointing out standing water to neighbors and landlords.
Safety note: keep candles and coils away from anything flammable, and never leave open flames unattended.
Quick answers
What is the fastest way to get rid of mosquitoes in my yard? Remove standing water today, then repeat weekly. Treat water you can’t drain with Bti. Yard sprays give only temporary relief.
Are mosquito dunks safe for pets and birds? The CDC says larvicides used according to label instructions do not harm people, pets, or the environment. Follow the dose on the label.
How long do mosquito dunks last? About 30 days, according to UC IPM.
Do citronella candles keep mosquitoes away? They may help a little in still air, per UC IPM. They do not replace removing standing water or using repellent.
What repellent does the CDC recommend? An EPA-registered product with DEET, picaridin, IR3535, OLE, PMD, or 2-undecanone. Don’t use OLE or PMD on children under 3.