How to Make a Gnat Trap With a Soda Bottle

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When the weather warms and windows are thrown open to let the cool breeze freshen the rooms, uninvited airborne guests also make their way into your home. A soda bottle fly trap or fruit fly bottle trap is easy to make and can have your indoor and outdoor spaces free of flying pests within hours of completing.


How to Make a Gnat Trap With a Soda Bottle
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How a Gnat Trap Works

The gnats are drawn to the scent of the sweetened bait and travel down the narrow opening of the inverted neck into the wide space of the soda bottle fly trap. Once inside the voluminous space, they have a hard time finding their way out through the funnel and drown in the water.


This works for most winged insects, including fruit flies, house flies (if the opening is large enough and the bait sweet enough) and whiteflies.

Bait to Consider

Typically, bait is a small piece of cut-up fruit of your choice and a small amount of water. Vinegar and sugar at a 1:1 ratio can also be used to draw gnats into the trap. Depending on the bait you use, the odor can become an issue, so take that into account when choosing a fly trap bait.

Baits that work best include:


  • Banana pieces
  • Rotten apple
  • Fleshy stone fruits cut in half
  • Ripe berries
  • Apple cider vinegar with a drop of dish soap

Gnats easily adapt and can become resistant to the original source of their attraction. Change up your bait if the number of gnats roaming around your home is getting worse.

Where to Place a Gnat Trap

A small gnat trap can rest neatly in a bowl of fruit where the gnats gather. A larger gnat trap can be placed by entryways or in large living spaces to attract errant insects that flit from room to room.


If fruit flies and gnats are an issue in a cabin or a garden, spread them around the area, spacing them about 3 feet apart. This will help to catch any critters before they have time to populate.

Gnat Catcher DIY

A correctly made gnat trap can noticeably cut down on the tiny germ carriers careening around your kitchen.

  • Cut the top off of a plastic soda bottle about two inches below the neck.

  • Pour in sweet liquid bait or fruit covered halfway with water. The bottle should be no more than half full with liquid to drown the flying insects.

  • Invert the cut top of the soda bottle back onto the main cylinder with the neck facing down.

  • Tape the pieces together to close off gaps and keep it secure.


Double-Sided Tape

A piece of double sided tape attached to a window can increase the effectiveness of your gnat trap. Flying bugs are naturally attracted to windows.

Place a homemade gnat trap next to the window with the double-sided tape, and you are sure to catch plenty of airborne pests.

This will also work when placed on metal siding or a plastic surface that can handle the sticky tape. Rubbing alcohol can remove any sticky substance left behind on the glass, wood or plastic surface.


Benefits of a Homemade Gnat Catcher

This type of trap is ideal if you have young children or four-legged friends who may find a gnat trap an interesting object to play with. The design ensures little fingers or curious noses won't get into a sticky, toxic, fly-filled mess that a commercial fly trap would involve. If it tips over, it won't create a big mess, and it is easily refilled.

You can decorate the gnat trap DIY container so it blends in with your home décor while still attracting the uninvited flying guests through the narrow funnel.



Kimberley McGee is an award-winning journalist with 20+ years of experience writing for a variety of clients, including The New York Times, Las Vegas Review-Journal Home section and other national publications. As a professional writer she has researched, interviewed sources and written about home improvement, interior design and related business trends. She earned a B.A. in Journalism from the University of Nevada, Las Vegas. Her full bio and clips can be viewed at

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