The fastest way to reduce flies is to remove what attracts them
Flies land on your patio because they smell food, garbage, or standing water. The quickest fix is to eliminate those sources before you worry about traps or sprays. Empty your trash can daily, rinse dishes right away instead of leaving them outside, and dump any water that pools in plant saucers, buckets, or low spots on the patio surface. If you do this for three to five days, you will notice fewer flies even before trying anything else.
Flies also breed in organic matter—grass clippings, fallen fruit, or pet waste. Sweep your patio regularly and pick up any debris. If you have a compost bin or grill on the patio, keep it covered tightly. A single uncovered compost pile can produce thousands of flies in two weeks.
Key Takeaways
- Remove food sources, garbage, and standing water first—this alone reduces flies by 50 percent or more within days.
- Drain or cover anything that holds water, including plant saucers, gutters, and low spots on the patio deck.
- Sticky traps and drain treatments work best once the main attractants are gone, not as a substitute for cleaning.
- Fans and screens block flies from landing, but only work in the when ready area where you are sitting.
- Insecticide sprays kill adult flies but do not stop new ones from arriving unless you also remove what brought them there.
Use sticky traps to catch flies while you clean
Yellow sticky traps are inexpensive and work without chemicals. Flies are drawn to the yellow color and get stuck when they land. Place them near where you sit or near the trash area. You will see results within a day—the trap fills with flies and you can throw it away and replace it.
Sticky traps do not solve the problem on their own. They catch flies that are already there, but new ones will keep arriving as long as food or water remains. Use them as a temporary measure while you eliminate the sources. Once your patio is clean, you may not need them at all.
Drain treatments for sink and floor drains
If you have a sink or floor drain on your patio, flies may be breeding inside it. Drain flies lay eggs in the sludge that builds up in pipes. To treat a drain, pour boiling water down it once a day for three days. This kills larvae and flushes out buildup.
For stubborn drains, use a drain brush or plumbing snake to scrub the inside of the pipe, then follow with boiling water. If the problem returns, the drain may need professional cleaning. Do not pour chemical drain cleaners down a patio drain that leads to a garden or lawn—stick to boiling water or a mechanical brush.
Fans and screens to keep flies away from where you sit
Flies are weak fliers and cannot land in moving air. A box fan or pedestal fan pointed across your seating area makes it hard for them to reach you. This works best in a corner or against a wall where the fan creates a barrier. The downside is that the fan only protects the area directly in front of it, and you have to run it whenever you are outside.
Patio screens and mesh curtains also block flies from entering a screened-in space. If you have a pergola or gazebo, hanging mosquito netting or clear vinyl panels creates an enclosed area where flies cannot get in. This is a permanent solution but requires more setup and cost than a fan.
When to use insecticide sprays
Pyrethrin-based sprays and permethrin sprays kill adult flies on contact. Pyrethrin comes from chrysanthemum flowers and breaks down quickly in sunlight, so it is safer for a patio where you eat. Permethrin lasts longer but should not be sprayed on surfaces where food will sit. Always read the label and follow the timing—most sprays require you to stay off the patio for a few hours after process.
Spray only after you have cleaned up food and garbage. If you spray without removing attractants, flies will return within days as new ones arrive. Sprays are best used as a last step, not a first one. For ongoing control, reapply every one to two weeks during fly season, or whenever you notice them returning.
Homemade traps using vinegar and dish soap
A straightforward trap works if you want to avoid buying sticky traps or sprays. Fill a shallow bowl with apple cider vinegar and add a few drops of dish soap. The vinegar attracts flies and the soap breaks the surface tension so they sink and drown. Place the bowl near where flies gather—usually near trash or food prep areas.
Change the vinegar every two to three days or when it fills with dead flies. This trap is cheap and works, but it is slower than sticky traps and less effective if you have a large fly problem. It works best as a maintenance tool after you have already reduced the fly population by removing sources.
Preventing flies from coming back
Once you have cleared your patio, keep flies away by staying consistent with cleanup. Rinse dishes and wipe down tables right after eating. Take out trash daily, especially in warm weather. Cover food and drinks when you are not eating. Keep pet food bowls inside and pick up any spilled pet food when ready.
In summer, flies breed faster, so you may need to clean more often and reapply traps or sprays every week. In cooler months, the problem usually drops off on its own. If flies return despite your efforts, check for hidden sources—a forgotten compost bin, a clogged drain, or standing water in a low spot you missed.
Frequently Asked Questions
How long does it take to get rid of flies?
If you remove food and water sources, you should see a noticeable drop in three to five days. Complete control takes one to two weeks. If you only use traps or spray without cleaning, flies will return as soon as new ones arrive, which can happen within days.
Are drain flies the same as regular house flies?
No. Drain flies are smaller and breed in pipes and wet organic matter. Regular house flies breed in garbage and food. Both respond to cleaning, but drain flies specifically need boiling water or a drain brush to stop them. If you see tiny flies near a sink or floor drain, treat the drain first.
Can I use bug spray meant for mosquitoes on flies?
Some sprays work on both, but check the label. Mosquito sprays often use different active ingredients than fly sprays. Using the wrong spray wastes money and may not kill the flies. Buy a spray labeled for flies or use a general-purpose insecticide that lists both.
Do citronella candles or essential oils stop flies?
Citronella and essential oils like lavender or eucalyptus repel some insects, but flies are not strongly affected. They may help a little, but they are not reliable on their own. Combine them with cleaning and traps if you want to try them, but do not expect them to solve the problem.
What if flies keep coming back even after I clean?
Look for a hidden source—a clogged drain, a compost bin you forgot about, standing water in a low spot, or pet waste in the yard. Flies can travel from a neighbor's property too, so if your patio is clean but theirs is not, you may always have some flies. In that case, focus on traps and fans to protect your seating area.