The tiny fruit fly is one of the most common flies found in homes. It is often brought indoors on fresh fruits and vegetables, and it sticks around because it can find plenty of food in a house. Fruit flies are 1/10 inch to 1/5 inch long and typically have red eyes, yellow-brown bodies, and black rings around their abdomens. They belong to the Drosophila genus and also go by the common names of vinegar flies, pomace flies, and wine flies. The fruit fly is not capable of causing damage to a home. It is just a great nuisance, especially when there are a lot of them.
As their name suggests, fruit flies feed on overripe fruits, rotting vegetables, and other foods they find in the garbage or even in drains. And as their other common names imply, they also feed on wine, vinegar, and pomace (the pulpy residue left from the crushing of fruits). Moreover, because fruit flies like the yeast in foods, they are often attracted to breads and other baked goods. Fruit fly populations usually explode in the late summer and fall because that's when many fruits are ripe and are being harvested. The average fruit fly lives around 30 days, and the female fruit flies can lay hundreds of eggs at a time.
3 Ways to Get Rid of Fruit Flies
Getting rid of fruit flies goes hand in hand with preventing them from multiplying. If you kill as many adult flies as possible while eliminating their food sources and breeding grounds, you're on your way to winning the battle.
Eliminate Food Sources
The first step to getting rid of fruit flies is identifying all potential sources that support them, then doing away with (or putting away) those sources. In addition to fruit and vegetables, these tiny flies like sweet stuff (like spilled juice or jelly), fermented stuff (open beer cans or wine bottles), and rotten stuff (slime inside garbage disposers and drains). For the same reasons, they also like garbage, recycling cans, and compost containers. Most fruits can be stored in the fridge (where flies can't get to them). All other food sources for fruit flies should be cleaned up or taken out.
Try Some Traps
DIY fruit fly traps are all over the internet, and they're all inexpensive and easy to make. Do they work? Sometimes. But they're so simple that it can't hurt to try. Traps range from a bowl full of vinegar to contraptions made from plastic soda bottles reminiscent of grade-school science projects. The idea is to set out some traps on the kitchen counter, wherever fruit flies hang out. The flies are attracted to the liquid in the trap, then they get trapped or they drown. You'll catch adults only; the young ones are eating and growing right on the food source, but catching a single adult can potentially prevent hundreds of new flies. You can also buy sticky fly traps designed for fruit flies. Many of these include a bait on the sticky surface to lure the flies.
Spray Them (If You Want)
Fruit flies usually are not enough of a nuisance to warrant spraying insecticide around your kitchen, but this can be a tempting option if they're driving you crazy. As with traps, it works only on the adults. Don't spray your food in an effort to kill young flies because you'll just ruin the food. While commercial sprays such as permethrin are effective on fruit flies, you can also spray them with 91-percent isopropyl alcohol (rubbing alcohol), using a fine-mist sprayer. Alcohol is a great sanitizer, and it doesn't harm most surfaces, but it can discolor some materials.
What Causes Fruit Flies?
Fruit flies get into your house by stowing away on fruits you bring in from the store or garden, or they simply fly in through open doors or windows, small cracks, or tears in window screens. Sometimes the screen mesh itself doesn't stop them because the mesh isn't fine enough.
Once they've found a good food source, adult flies lay eggs (up to 500 at a time!) directly onto the source. The next day (in 24 to 30 hours), the eggs become larvae, then pupae, and finally flying adults in the span of about one week. Fruit flies reproduce and feed on many common items in a typical kitchen, including:
- Ripe, rotten, and decaying fruit and vegetables
- Spilled juices and other sugary liquids
- Trash cans
- Recycling containers
- Garbage disposers
- Mop buckets
- Beer, wine, liquor, and other fermented beverages
- Fruits and vegetables from a home garden, including tomatoes, grapes, melons, squash, onions, and potatoes, among others
How to Prevent Fruit Flies In the Home
As with most flying insects, control of a fruit fly infestation is best achieved by limiting the flies' ability to feed and breed. This involves:
- Refrigerating fruits and vegetables that can tolerate refrigeration
- Discarding overly ripe, damaged, or decaying fruits and vegetables
- Cleaning any spilled juices, sodas, wines, or other liquids
- Washing beverage containers before recycling them
- Regularly emptying and cleaning trash and recycling containers and the areas around them
- Covering fruits and vegetable (those not stored in the fridge) with mesh covers
Once you have sanitation under control, often the best approach is to wait for the fruit fly population to diminish. Particularly for outdoor infestations, such as around trash containers, the arrival of cold weather can cause a fruit fly population to disappear as rapidly as it seemed to grow in the warm weather. But regardless of where the infestation is, if the flies have no food, they likely won't be a problem for long.
Can fruit flies fit through window screens?
Fruit flies typically cannot fit through mesh on standard window screens, which have a size of 18 x 14 openings per inch. The minimum mesh size to keep out the flies is 16 openings per inch.
Can fruit flies make you sick?
Fruit flies are not considered dangerous, even if they are ingested. However, they can spread bacteria and microorganisms from one place to another and therefore can potentially contribute to food-borne illness, although this can be hard to trace
Do I have to throw out food that has attracted fruit flies?
You can eat fruits and vegetables that flies are hanging around, but first cut away any damaged, bruised, or rotted portions (that's where the flies are most likely to lay eggs), and wash the items well before eating them.
Center for Disease Control. 2021. Chemical Disinfectants | Disinfection & Sterilization Guidelines | Guidelines Library | Infection Control | CDC.
Black EP, Hinrichs GJ, Barcay SJ, Gardner DB. Fruit Flies as Potential Vectors of Foodborne Illness [published online ahead of print, 2018 Feb 23]. J Food Prot. 2018;509-514. doi:10.4315/0362-028X.JFP-17-255