Fruit Flies: What to Pour Down Your Drain

Fruit flies are pesky pests that you can find around your home all year round, but more in late summer and fall. You can pour a drain cleaner like Green Gobbler, or your own mixture to help get rid of them. Read on to learn more about these pests!

Despite their persistent presence, fruit flies don’t bring any specific illnesses to the party. However, they do like to carry around bacteria from their not-so-hygienic breeding sites and spread it all over your food and surfaces, turning your kitchen into their own personal buffet of infectious microorganisms. How thoughtful of them!

Now, what do these party-crashers find so attractive? Overripe and rotting fruits and vegetables, of course! So, when you spot these tiny terrors, the first step is to play cleanup crew and dispose of any mushy produce while giving your kitchen a good scrubbing. Time to clean up their mess!

Unfortunately, sometimes the flies do not always go away once the fruit is gone and the kitchen is clean. Fruit flies can find a perfect home in your drains. So, if you still see fruit flies around your sink after cleanup, you may have an infestation of fruit flies inside your drains.

How do fruit flies get in a drain?

These flies gain access through cracks in the wall, damaged seals around doors and windows, or eggs laid inside fruits or veggies from the grocery store.

Once inside your home, the adult flies seek ideal places to live and reproduce. Because they are dark, moist, and full of food residue (organic material buildup), drains, plumbing systems, and garbage disposal provide an ideal breeding ground for fruit flies.

When you do dirty dishes, leftover food particles and other organic matter can get caught in the pipes. This slime buildup in the drains offers a food source and a perfect place for fruit flies to live and reproduce.

How to eliminate fruit flies in your drain

It can be challenging to eliminate fruit flies because they live longer than the average insect—the lifespan of a fruit fly is 40 – 50 days.

They also breed in sizable numbers—adult female fruit flies can lay up to 500 at a time, which hatch in 24 to 30 hours, leaving you with generations of flies to deal with in a short time. To effectively kill and eliminate fruit flies, follow the following steps:

Proper identification

Proper identification of the pest you are dealing with is the first step towards successfully eliminating them. Adult fruit flies and the pupae are the easily noticeable signs of fruit fly activity.

You can easily spot adult flies buzzing around the kitchen near overripe or decaying fruits and vegetables. You can also see them around your trash can, potted plants, or empty wine/liquor/beer cans and bottles.

Mature fruit larvae crawl out of the breeding material to pupate in nearby dry spots. While it is easy to mistake the pupae for cockroach or rodent droppings, you can quickly identify them by the horns on one end of the pupae. If you see flies coming from your drain, it could be fruit or drain flies.

Fruit flies vs. drain flies

It’s easy to confuse fruit flies and drain flies because they tend to have the same appearance, often behave similarly, and can be found in the same places.

The common fruit fly may have a yellow-brown (tan) color with black stripes or spots on the upper side or back of its abdomen. It has a rounded head, large, distinct red eyes, and a short antenna. Fruit flies measure about 3mm in length and 2mm in width, but the female is slightly larger than the male.

Drain flies are sink, filter, sewer flies, or sewer gnats. Their color ranges from light tan and pale gray to black, measuring about 1.5mm to 5mm long. They have an antenna, and their body and wings are covered with long hairs that give them a fuzzy look.

Drain fly wings often appear too large for their bodies, and they are poor fliers, hopping from surface to surface instead of buzzing around.

Get rid of overripe fruits and veggies

If you expose a fruit bowl filled with overripe fruit, vegetable, or leftover food, your kitchen becomes a hotspot for these flies. So, keep overripened fruit and veggies in sealed containers in the refrigerator.

Consider moving potted flowers or your tabletop herb garden outside because fruit flies thrive on nectar and love the moisture in the soil.

Clean your kitchen, sink, drain, and garbage disposal

Clear your kitchen to remove clutter, and properly dispose of trash, including empty beer or wine bottles and cans. Then, use standard cleaning solutions to clean. Use a pipe brush to scrub inside drains, then rinse with hot water. You can also use other DIY methods or store-bought products to clean the inside of the drains to get rid of fruit flies.

Get professional help

When all fails, consider getting professional service from a pest control specialist. A plumber will free your system of clogs and debris and fix any problems to avoid reoccurrence.

What to pour down the drain for fruit flies

  • Boiling water: If you notice fruit flies coming from specific kitchen sink drains, pour boiling water into them. Boiling water can eliminate the organic waste the flies are attracted to. It can also help kill the fruit flies and their eggs. Do this multiple times weekly for several consecutive weeks to ensure effective elimination.

Add white vinegar to the boiling water for a more powerful effect. Repeat this a couple of times until the flies are eliminated.


If you have PVC pipes, it’s important to note that pouring boiling water repeatedly can damage them. Cracked PVC pipes can be a more significant and costly problem than fruit flies.
  • Vinegar and baking soda: This combination unclogs your drains to eliminate the organic matter. Pour boiling water, followed by baking soda and vinegar, into the drain in question. Cover the drain for 10 minutes and pour more boiling water again.

You can also make a solution of a cup of vinegar, 1/2 cup of baking soda, and 1/2 cup of salt. Pour this down the drain, leave it overnight, and in the morning, pour boiling water to flush out the drain.

  • Hydrogen peroxide: When hydrogen peroxide reacts with the bacteria, it will foam and kill adult flies and their eggs. Pour 1/2 a cup of hydrogen peroxide into the drain.
  • Drain cleaners: Drain cleaners can help dissolve the buildup and aid the physical cleaning of all your drains, including the kitchen and bathroom drains, destroying breeding grounds. Examples of drain cleaners include Drano, Green Gobbler (enzyme cleaner), Bio-clean, and Invade Bio Drain. When using any drain cleaner, read the instructions for safe and effective use first.

Note: Pouring bleach or other harsh chemicals down the drain is rarely, if ever, effective in eliminating fruit fly breeding grounds.

You can use bug sprays, aerosols, and store-bought and homemade traps like apple cider vinegar, wine, and rotten fruit fly traps to kill adult flies.

How to prevent fruit flies in the drain

The most effective way to keep fruit flies and other flies away from your drain is through regular maintenance to ensure no clogs or organic matter build up. Keep your home clean, remove any leftover food from the kitchen, empty your trash cans regularly, and clean them properly.

Also, wash produce immediately after you get it to the house and dispose of any fruit or other produce past their prime, including cut flowers. Repair damaged window and door seals and other possible entryways.

Last update on 2024-06-12 / Affiliate links / Images from Amazon Product Advertising API