Figuring out how to eliminate flies outside can make your yard more enjoyable through the summer and 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.
These are the primary approaches for how to get rid of flies outside:
- Eliminate their food sources.
- Seal up cracks around buildings.
- Encourage natural predators like birds, bats, and frogs.
- Trap the flies with cone traps or resin sticks.
- Use fans as a deterrent.
- Light candles since smoke is a repellant.
- Make DIY fly strips using scented oils.
- Trap them with apple cider vinegar.
What Do Flies Look Like?
A “fly” is any insect in the Diptera order of insects, identified by only one 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.1
- Common house fly: Dull gray fly, about 1/4-inch long with four dark stripes on the middle section (thorax) of its body; larva are white, legless maggots; hatch from the eggs and grow to about 1/2 inch
- Cluster flies (Pollenia rudis): Larger than a housefly (almost 1/2-inch long); silvery-black checkered body; short golden or yellowish hairs on their lower bodies (house flies do not have them); back wings cross when not flying
- Fruit flies (Drosophila melanogaster): Tiny (1/8-inch) with yellowish-tan bodies, transparent greyish wings, dark grey rings around their abdomen, and bright red eyes
Signs of Fly Infestation
A couple of flies is not likely an infestation, but it can turn into one once you start to see many buzzing around. Look for other signs that might point to a problem brewing:
- Clusters of small, tiny, pinhead-sized spots: These spots, called flyspecks, may be a sign of fly excrement, usually found near the food source or nesting spot
- Swarms or higher numbers of flies: Swarms will occur near a significant food source or potential nest
- Maggots: Female lay their eggs in garbage cans, rotting food, and manure. Favorite spots include leftover food on a counter, a forgotten trash bin, or feces in a litter box.
8 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.
1)Eliminate Food Sources and Breeding Areas (Most Effective)
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 pooling areas, stagnant water, and other excessive moisture around the yard.
- Keep compost piles farther from the house to keep flies to a minimum.
2) Seal Buildings
- Seal cracks around windows and doors where flies may enter your house, shed, garage, or other buildings.2
- Use well-fitted, small-mesh, well-maintained screens on all doors and windows
3) Encourage Natural Predators
- Place a few bird and bat houses and a birdbath around your property to encourage fly-eating birds and bats.
- Welcome frogs and other small amphibians into your garden; these animals also consume adult flies and their larvae.
4) 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 (“flypaper”) 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 also be used there.
- Hang ultraviolet light traps in alleyways, beneath trees, and around animal sleeping areas and manure piles to attract and kill flies.
5) Use Fans
Set up an oscillating fan near your grill or picnic table. Flies don’t maneuver well in strong breezes, so this works well to keep them at bay. A permanent overhead fan is also an option if your deck or patio has an overhead structure.
6) Light Candles
Surround your patio or porch with citronella candles, comprised of aromatic oils distilled from lemongrass, which will repel both flies and mosquitoes. In addition to the scent, candles produce smoke, which is a repellent for most flying insects.
You may need to light several candles to repel flies effectively.1
7) Make DIY Fly Strips
- Make 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.
8) Trap Flies With Apple Cider Vinegar
Vinegar attracts flies, particularly apple cider vinegar. Flies smell the acetic acid in vinegar, the same smell of fermentation when fruits decompose.
Set out a container with vinegar and some dish soap. The vinegar lures the flies, and the dish soap causes the flies to sink and die. You can put it in a bowl, an inverted cone trap, or an empty soda bottle trap.
What Causes Flies Outdoors?
Flies appear in outdoor locations wherever there are food sources (decaying plant and animal material) and moisture. Darkness also enhances the breeding, hatching, and development of larvae into more flies.
Here are most of the possible causes of a fly infestation outside:
- Fresh excrement or dead matter: Flies can’t resist fresh poop or carcass since its warm and wet, which is easier to eat and lay eggs upon; pick up pet poop or dead animals outside to avoid a fly problem
- Trash cans and compost piles: Decomposing materials are the perfect meal and nesting spot; avoid leaving trash uncovered or strewn about for easy access.
- Carefully select your fertilizer: Some fertilizers use manure or compost as an ingredient; these fertilizers can be fly magnets.
- Water source: A reliable, unchecked water source like a leaky pipe is a haven for flies; flies can only lay their eggs on moist surfaces and need moisture to eat
- Preparing for hibernation: Some flies may swarm near the outside homes in late summer or early fall, looking for ways into a warm home’s open doors, cracks in the facade, vents, siding, and eaves.
How to Prevent Flies Outdoors
Preventing flies is mostly denying them the food and moisture necessary for reproduction. This, combined with various trapping methods, natural predation, and repellant methods, can keep fly populations under control.
Ensure all your exterior trash is stored in clean, sealed receptacles, and consider changing outside white lights with insect-resistant yellow bulbs.
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 challenging to control in outdoor locations.2
That said, a proper fogger insecticide can be an effective temporary measure to repel flies and stinging insects if applied an hour or so before a picnic or outdoor gathering.
Properly labeled residual pesticides can be used where flies are seen to rest, such as on the outside surfaces of homes and overhangs. If insecticides are used, they may have to be reapplied every two to four weeks during warm weather. When using residual insecticides, call an exterminator to handle the task.
When to Call a Professional to Treat a Fly Infestation
Flies can spread diseases like cholera, salmonella, and typhoid fever.3 Control is imperative. But, if a fly swatter is too inefficient a tool for the task at hand, get some help. A professional can root out the source of the infestation or get rid of the problem quickly and efficiently.
A pest management professional is also the best person to apply residual insecticides since they may be subject to restricted use or be otherwise unavailable to homeowners.
Do flies bite?
The horse-fly (Tabanus spp.) and the black fly (various genera) 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. They can spread bacteria, fungi, and viruses, including the germs that cause anthrax, typhoid, stomach ulcers, cholera, dysentery, and tuberculosis.4 Remember this the next time you see a fly land on the hamburger that’s just come off the grill.
- What scents do flies dislike?