How to Make a Fly Trap From an Empty Soda Bottle

1. Mark a Cutting Line

   Draw a line all the way around the bottle using a permanent marker, just below the tapered neck.

2. Cut the Top off the Bottle

   Use a sharp knife with a serrated blade to cut along the line, severing the top of the bottle. Cut on a cutting board so there's no damage to your counter or table surface.

3. Assemble the Fly Trap

   Remove the soda cap, then flip the top of the bottle upside down and slide it into the bottom of the bottle, like a funnel, to complete the fly trap.

   Tip

   You can keep the cap on the bottle, but if you do, you will need to punch a large hole in it so the flies can get down into the trap. Keeping the cap on will further prevent the flies from finding their way out.

4. Bait the Trap

   Remove the "funnel" from the bottle so you can place the bait. Choose a bait for your trap.

   Flies are attracted to nearly any decaying organic material. Though it is meat and feces that flies seek out to lay eggs (the larvae, which we know as maggots, will immediately feed on those materials when they hatch from fly eggs), few people will want to use that as indoor bait. Consider these pleasant ideas for bait:

   • Slightly over-ripe fruit
   • A 50/50 water and sugar mix
   • Water mixed with honey or maple syrup for a stickier solution
   • Fruit-scented dish soap

   If you are using this trap outdoors, use a more pungent bait. To keep bees out of your indoor or outdoor trap, add a splash of vinegar to the mix.

   Tip

   You can also trap wasps with this method since they are drawn to sweets as well.

5. Make a Handle for the Fly Trap

   If you prefer a hanging trap, use a hole punch to punch two holes on opposite sides at the top of the bottle. Make sure they go through both layers of the trap. Then thread a piece of wire through the holes, crimp the ends, and your trap is ready to hang.

   Tip

   If you notice gaps between the edges of where the "funnel" rests in the bottom of the bottle, tape them up just in case a sly fly decides to squeeze out and escape.

Tips to Make the DIY Fly Trap Work

There are certain times of year when flies are more prevalent. In colder climates, this is often in the spring as the sun begins to warm the walls of the home, bringing out the first flies from their winter stupor. Houseflies have a predictable lifecycle that can include many hatch cycles each season, so if you set out your trap when the first flying pests appear, you stand a good chance at minimizing fly outbreaks, since you'll be trapping most of them before they have a chance to lay eggs that fuel the next cycle.

In some environments, trapping may be an almost constant affair. In warm climates near animal pens or pastures, for example, flies may be an almost constant presence, and you'll want to keep the DIY fly traps in place for most of the warmer months.

To maintain the trap, empty the dead flies and re-bait your trap regularly. If you decide to use meat or animal droppings (chicken litter, rabbit pellets) as bait, you'll also need to destroy any larvae that you find in your trap. Rinsing the bottle out with hot water should do the trick, or just create a fresh new trap.