If you're like me, trying to grow a garden in a shady yard in a humid and cool climate, you will probably find yourself declaring war on slugs. Slugs are one of the most destructive and difficult garden pests to control. There are endless ways to kill slugs in your garden, but many of them involve a lot of time and effort and are either toxic, can destroy the soil in your garden or simply don't work very well. So where should you start in your war on slugs? To save you time and wasted effort, I'm only going to share my experience with the methods that I've tried.
Iron Phosphate Bait - This is the most successful method that I've tried. It's safe to use on vegetable gardens and around children and pets. I also found it to be the least labor-intensive method to use because each application lasts up to two weeks, and you don't need to reapply it every time it rains or you water your garden. It takes a couple of days before any reduction in slug damage is noticeable, but it does work.
Diatomaceous Earth - Here is another product that's safe to use on your vegetables and in areas where children and animals might come into contact with it. Just be sure not to inhale it. Although it does kill slugs, it also can kill some insects that are beneficial to your garden. The other drawbacks to using diatomaceous earth are that your garden won't look pretty when it's covered with the white powder (like a bad case of garden dandruff), and you'll need to reapply it after watering or rain.
Hand Removal - Picking individual slugs off the plants was by far the most labor-intensive, not to mention disgusting, method I tried. Slugs come out after dark and follow their previously laid slime trail up the stems and onto the tender leaves of your plants. At this time, you can pluck them off and dump them into a bowl of one part salt to eight parts water, which will kill them. I only had the patience (and stomach) to try this method for a few nights, and even though I collected dozens of slugs, I didn't see that it made any difference at all.
Beer Traps - This method involves sinking a small container filled with beer into the soil of your garden, so the lip of the container is level with the ground. The slugs love the yeast in the beer, and when they try to drink the beer, they fall in and drown. Make sure that the container is deep enough for the slug to drown in and that you clean out the dead slugs regularly. Some people swear by this method, but it didn't work very well for me. Perhaps the slugs either found a way back out of the beer, or they didn't enjoy the particular brand I chose. According to a study done by the Colorado State University, slugs prefer Kingsbury Malt Beverage, Michelob and Budweiser. I guess they didn't enjoy the Heineken I left for them, as the beer trap was the least successful of all the methods I tried.