How to Build a Garden Slug Beer Trap

by Gary Pilarchik LCSW-C

Why Build A Slug Beer Trap?

Click to enlarge. Bok Choy - damaged by slugs

 

The evidence is my Bok Choy! Bok Choy!. No it's not a war cry to attack and destroy slugs. It is the casualty. All the holes in the leaves are from slugs. You will notice coarse sand around the base. It didn't help. You will notice pulverized lime on the leaves. It didn't help. So I added beer traps.

The truth is... managing slugs in the garden takes a multiple step approach. This Knol shows you one way to help reduce the number of slugs in your garden.

The Supplies

Slug Trap Supplies

You can purchase foil tins at your local grocery store. The shape and depth of the tins don't really matter. I suggest tins that are 1 - 3 inches deep. Any bottle of beer and some yeast is also needed to build the trap.

The slugs are attracted to the yeast. A little extra yeast sprinkled in with the beer helps to bait the trap.

Selecting the Location

Cabbage and Bok Choy

Select a location that is fairly close to the crops you want to protect. I tried protecting the above vegetables with coarse sand. The heads in the middle are Bok Choy or Chinese cabbage. They were fiercely attacked by the slugs and I am keeping them as a casualty crop. I let the slugs attack them and they pay less attention to my other crops. Right between the cabbages is where I will build the beer trap.

Placing the Tin

Place the tin at ground level

There isn't much to say but dig a hole and drop the tray in. The edges of the tin should be flush with the garden soil. We want it to be easy for the slug to crawl or fall into the trap. Once they fall in, they drown.

Baiting the Trap

Fill the beer trap with beer and a bit of yeast

Fill the trap about 3/4 the way full with beer and drop in a bit of yeast. The trap is set.

Trap Locations

 

Protection for my spinach, turnips and parsnips

Two traps for my cabbage patch

A trap with my other Bok Choy plot

Maintaining the Traps

I found I have to change the beer every 2-3 days. Three days might be pushing it. If you wait longer it doesn't do much more than sour and smell bad. Don't forget to add a pinch of yeast to the trap when you change the beer.

Beer traps work well and should be part of your attack in your war against slugs. I have not found a way to kill every slug but find you can really decrease their numbers in the garden.