Figuring out how to get rid of flies outside can make your yard more enjoyable through the summer and also reduce the number of flies that sneak into your home. There are two approaches to getting rid of outside flies. You can try to eliminate and repel them from the immediate area where you are trying to enjoy outdoor activities, but it's a temporary solution. Or, combat flies at the source where they are breeding. Read on to understand what causes flies outdoors and tips on how to keep them away.
What Is a Fly?
A "fly" is any insect in the Diptera order of insects, identified by the presence of only a single pair of operational wings, rather than the two pairs found in many other insects. The ordinary housefly (Musca domestica) is the small, buzzing insect with bulging eyes that commonly bothers us.
7 Ways to Get Rid of Flies Outdoors
There are many dozens of species of flies, but eradication methods are largely the same for all of them.
Eliminate Food Sources and Breeding Areas
Clean up or eliminate any sites where the flies are seen to be living and breeding as well as any that are attracting them to feed:
- Use tight-fitting lids, and clean trash bins regularly. If you use plastic bags, ensure they are well sealed.
- Pick up pet feces regularly, and remove any dead or decaying plants.
- Keep dog kennels clean, pick up food after the dog's feeding time as much as possible, and clean up any spilled food or water.
- Eliminate areas of pooling, stagnant water, and other excessive moisture around the yard.
- Keep compost piles far from the home and properly managed to keep flies to a minimum.
- Seal cracks around windows and doors where flies may enter your house, shed, garage, or other buildings.
- Use well-fitted, small-mesh, well-maintained screens on all doors and windows
Encourage Natural Predators
Many birds and virtually all bats feed heavily on flying insects, including houseflies. Birds also eatmaggots and larvae, offering preemptive control of flies. Bats are typically night hunters, and they can eat huge quantities of flies in the early dusk hours.
Trap the Flies
- Use inverted cone traps containing fly food attractants. (The attractants can be very foul-smelling, so the traps should be placed away from occupied structures.)
- Place insecticide-impregnated resin strips ("fly paper") on the inside of garbage can lids to attract and eliminate flies that get into the trash. If your dumpsters seal tightly, fly paper strips can be used there as well.
- Hang ultraviolet light traps in alleyways, beneath trees, and around animal sleeping areas and manure piles to attract and kill flies.
Set up an oscillating fan near your grill or picnic table. Flies don't maneuver well in strong breezes, so this works very well to keep them at bay. If your deck or patio has an overhead structure, a permanent overhead fan is also an option.
Surround your patio or porch with citronella candles, comprised of aromatic oils distilled from lemon grass, will repel both flies and mosquitoes. In addition to the scent, candles produce smoke which acts as a repellent for most flying insects.
You may need to light several candles to effectively repel flies.
Make DIY Fly Strips
- Make your own fly-repellent strips by soaking strips of cloth with scented oils, such as clove, lavender, lemongrass, citronella, eucalyptus, rosemary, or mint.
- Tie these onto tree branches or railings, the scent is remarkably effective at repelling flies.
What Causes Flies Outdoors?
Flies appear in outdoor locations wherever and whenever there are food sources (decaying plant and animal material) and moisture. Darkness also enhances the breeding, hatching, and development of larvae into more flies.
How to Prevent Flies Outdoors
Preventing flies is mostly a matter of denying them the food and moisture necessary for reproduction. This, combined with various methods of trapping, natural predation, and repellant methods, can keep fly populations under control.
Using Traditional Spray Pesticides
Chemical control should not be used unless all other methods have failed because flies have become resistant to many insecticides. This has steadily made fly populations more difficult to control with such chemicals. The winds and air patterns also make these sprays difficult to control in outdoor locations.
That said, a proper fogger insecticide can be an effective temporary measure to repel flies and stinging insets if applied an hour or so before a picnic or outdoor gathering.
When using any pesticide, be sure to read the product label and follow all directions. Make sure to store the product safely, away from where children or pets can reach them. Chemical pesticides are best regarded as a last resort measure, used with great care. Remember that most of these products will also kill beneficial insects, such as pollinator bees. Make sure that no insecticide contacts food or areas where food will be prepared or consumed.
Properly labeled residual pesticides can be used in areas where flies are seen to rest, such as the outside surfaces of homes and overhangs. A pest management professional is the best person to apply these residual insecticides, since they may be subject to restricted use or be otherwise unavailable to homeowners.
If insecticides are used, they may have to be reapplied every two to four weeks during warm weather.
Do flies bite?
The horse-fly (Tabanus spp.) and the black fly (various genera) both can inflict painful bites. The ordinary housefly, which is more common, does not bite.
How long do flies live?
Standard houseflies typically live between 15 and 25 days.
Do flies carry disease?
Flies are rightly considered rather filthy insects because they actively feed on feces and other decaying matter. As a result, they can spread a wide variety of germs, including the various bacteria that cause anthrax, typhoid, stomach ulcers, cholera, dysentery, and tuberculosis. This is worth remembering the next time you see a fly land on the hamburger that's just come off the grill.
Gerry, A. C. Pests of Homes, Structures, People, and Pets: Flies. University of California Agriculture & Natural Resources Statewide Integrated Pest Management Program, 2015.
"Flies." University of Minnesota Extension. Extension.Umn.Edu, 2021
Khamesipour, Faham, et al. “A Systematic Review of Human Pathogens Carried by the Housefly (Musca Domestica L.).” BMC Public Health, vol. 18, no. 1, Dec. 2018, p. 1049. DOI.org (Crossref), https://doi.org/10.1186/s12889-018-5934-3. doi:10.1186/s12889-018-5934-3