This page is part of the “DEFEND” section of the Three Ds Pest Control program, which is a gradual three stage approach to protect vegetables from pests that is designed to minimise the use of pesticides. DEFEND is when you actively kill pests attacking your plants, but only with environmentally friendly methods and only after DETER methods have failed. For an overview of the Three Ds Pest Control program click HERE.
Beer traps are a traditional and environmentally friendly way of killing slugs and snails.
Essentially they are a beer filled container that is used to first lure then kill slugs and snails. The sweet sickly smell of the beer is the attractant and the alcohol in the it is the poison. Slugs and snails that drink the beer become extremely sick and end up slipping into the beer and drowning.
While beer traps are effective at killing small slugs they aren’t as successful at killing large snails. They are also fairly high maintenance as the beer has thrown out and replaced with fresh beer about every two weeks.
There are commercially available beer traps on the market but you can also make your own traps.
MAKING YOUR OWN BEER TRAP
- GET A SHALLOW WATERTIGHT CONTAINER AND BURY IT IN YOUR VEGETABLE BED SO THAT THE LIP OF THE CONTAINER IS AT GROUND LEVEL
- FILL IT TO THE TOP WITH FULL STRENGTH BEER
Full strength beer has a higher alcohol content and it’s the alcohol that is the poison.
- PLACE TWO PIECES OF WOOD OR TILE EITHER SIDE OF THE CONTAINER SO THAT THE TOP OF THE WOOD/TILES SITS 2 OR 3 CM ABOVE THE TOP OF THE CONTAINER
- SIT A LID OF SOME SORT ON TOP OF THE PIECES OF WOOD/TILES TO COVER THE TOP OF THE CONTAINER.
The lid is to stop rainwater diluting the beer.
A problem with beer traps is that, compared to alternatives like snail pellets, beer is expensive. A cheaper alternative is to create your own alcohol with the use of fermented sugar.
To make fermented sugar simply mix a few tablespoons of sugar with some warm water and add a couple of teaspoons of powdered yeast. The fermentation that occurs will create the poisonous alcohol.
While fermented sugar is slower to act than beer it is a lot cheaper and, if the fermentation is strong enough, just as effective.
A commercial beer trap that is readily available and nurseries and hardware stores
An alternative way to make a beer trap is to use a 2 litre milk bottle. Make a long horizontal cut with a smaller vertical cuts on one side and bend the edges out. Fill with beer or a fermented sugar mixture and lay the bottle so as the bottom flap forms a ramp for the slugs and snails to climb up.
Iron EDTA complex pellets are a much more environmentally friendly than the more common Metaldehyde pellets. The pellets are marketed as safe for cats, dogs and birds. And, as they break down into nutrients for soils and plants as they decompose, they are also safe for earthworms.
Their down side is that they cost more, break down more quickly and are slower to kill slugs and snails than Metaldehyde pellets. However they still represent a much better alternative to Metaldehyde pellets and are more effective and involve less maintenance than beer traps.
Iron EDTA pellet box. The annoying thing about the packaging is that it looks like a standard Metaldehyde pellet box, even though the contents are very different.