A wax moth trap is a simple homemade device that lures adult wax moths away from your beehives before they can lay eggs inside. The most common version uses a 2-liter soda bottle filled with a fermenting sugar and vinegar mixture that attracts moths at night. While traps won’t eliminate wax moths entirely, they reduce the number of egg-laying females near your apiary and work best as one piece of a broader protection strategy.
How to Build a DIY Wax Moth Trap
The standard trap takes about five minutes to make. Start with an empty 2-liter plastic soda bottle and cut a hole roughly 30mm (about 1.25 inches) wide at the shoulder, right where the curved top meets the straight side of the bottle. Moths fly in through this hole and can’t easily find their way back out.
For the bait, combine these ingredients inside the bottle:
- 1 banana peel (push it in through the top)
- 1 cup white vinegar
- 1 cup sugar dissolved in 2 cups warm water
After adding those ingredients, top off the bottle with enough water to fill it about three-quarters full and screw the cap back on. To speed up fermentation, add a tablespoon of dry yeast mixed with warm water before sealing. The yeast gets the mixture actively bubbling faster, which produces the volatile compounds that draw moths in. Tie twine or heavy string around the bottle neck and hang it near your hives, ideally a few feet away so you’re intercepting moths before they reach the entrance.
Replace the bait every one to two weeks, or sooner if it stops smelling strongly fermented. In warm weather the mixture breaks down faster. You’ll find the traps collect the most moths during evening and nighttime hours, when wax moths are most active.
Why Traps Only Partially Work
Wax moth traps rely on the fermenting bait to mimic some of the chemical signals moths use to find food sources. But wax moths are more complex in how they locate mates and nesting sites. They use multiple pheromones to find each other, and greater wax moths also use ultrasound as part of their mating behavior. A fermentation trap captures some wandering adults, but it can’t replicate the full suite of signals that draw moths to a hive. Commercial pheromone traps have been tried with limited success for the same reason.
Think of traps as population reduction, not population elimination. They’re most useful in warm months when moth pressure is highest, and they work best when combined with other protective measures for your stored comb and active hives.
Two Species, Same Problem
The greater wax moth is the primary pest beekeepers worry about. It’s larger and more destructive, tunneling through brood comb and leaving behind a mess of silk webbing and frass. The lesser wax moth is smaller but follows a similar life cycle. Where both species coexist, the greater wax moth dominates the brood comb while the lesser wax moth feeds on debris along the hive floor.
One key difference: the lesser wax moth tolerates cooler climates better than its larger cousin, so beekeepers in northern regions aren’t necessarily safe from either species. Both thrive in warm conditions and become most destructive in stored comb that isn’t protected. At temperatures around 39°F (4°C), lesser wax moth activity drops dramatically but the moths aren’t killed. It takes sustained exposure to about minus 7°F (minus 20°C) for 24 to 48 hours to kill all life stages of both species.
Freezing and Heating Stored Comb
Trapping moths near your hives is one thing. Protecting stored frames over winter or between seasons is another, and temperature treatment is the most reliable method. Freezing kills every life stage, from eggs to adults, at the following exposures:
- 2 hours at 5°F (minus 15°C)
- 3 hours at 10°F (minus 12°C)
- 4.5 hours at 19°F (minus 7°C)
A standard chest freezer easily reaches these temperatures. After freezing, store the frames in sealed plastic bags or airtight containers so moths can’t re-infest them. Heat treatment also works: 80 minutes at 115°F (46°C) or 40 minutes at 120°F (49°C) kills all stages, though you risk softening or warping the wax if temperatures climb too high.
Biological Sprays for Drawn Comb
If you have a lot of drawn comb in storage, spraying frames with a biological larvicide is a practical option. Products like Certan and DiPel DF contain naturally occurring bacterial proteins that are toxic specifically to caterpillars and moth larvae. They have no effect on bees or other pollinators.
The application is straightforward. Dilute the product (Certan uses a 1:20 ratio in water, so a 5% solution) and spray both sides of each drawn frame with a pressurized hand sprayer fitted with a fine nozzle. About 10 ml per side per frame provides adequate coverage. When wax moth larvae hatch and begin feeding on the treated comb, they ingest the bacterial protein and die. The treatment doesn’t repel adult moths or prevent egg-laying, so it works as a second line of defense after trapping and proper storage.
Combining Traps With Other Defenses
No single method handles wax moths completely. The most effective approach layers several strategies together. Hang fermentation traps near your apiary during the active season, from late spring through early fall in most climates. Keep your colonies strong, since a healthy hive with a large bee population patrols its own comb and destroys wax moth eggs before they hatch. Weak or queenless colonies are the ones most vulnerable.
When you pull frames for storage, freeze them promptly before any eggs already present can develop. Store treated frames in sealed containers or stacked supers with no gaps. If you’re storing large quantities of comb, spray with a biological larvicide as added insurance. The trap outside catches some adults, the strong colony handles what gets past the trap, and temperature or biological treatment protects anything not on an active hive. Together, these measures keep wax moth damage to a minimum without chemical fumigants.