Garden slugs live their best lives in cool, damp weather. And once they've established themselves in your garden, they will help themselves to anything you put in the ground, from hostas to lettuce and basil, or flowers like marigolds.
Luckly, there are multiple pesticide-free ways to control slugs, from preventative measures to removing them after they're established.
Slug prevention
Prevent slugs from ever inhabiting your plants and flowers in the first place just by changing up how you arrange your gardens. By planting things in raised beds and removing mulch from between them, you've removed slugs’ and snails’ favorite crash pads.
By growing plants, herbs and flowers in raised beds, and spacing those plants farther apart, this also helps the soil in between to dry out. This can create an ecosystem that slugs don't like so they won't take hold in the first place.
Non-conventional slug deterrents
If you know someone with some raw sheep's wool, you could try this method used in some English gardens: they mulch around hosta plants using tufts of raw wool. The scratchiness and tannins in the wool work to create a barrier around the plant that deters slugs and snails. They won't cross over it, and that protects the plants.
A "beetle bank” is another inventive idea to try. Essentially, it's a circular raised bed, measuring about 4 feet in diameter and a foot or so tall.
Inside that raised bed, plant a selection of bunching grasses like bluestems and sea grasses. These types of plants attract the black ground beetle, which is a voracious eater of slugs and snails. The beetles hide in the tall grasses of your "beetle bank" during the day and once night falls, they go slug and snail hunting!
Another technique to combat snails and slugs in your garden is to leave clay pots and containers upside down. These dark spaces make great hiding places for toads and snakes, who love to eat snails and slugs.
The "beer trap" method is an old favorite, too. Create your own by pouring a small amount of beer into a bowl, then push the bowl down into the garden soil between your plants.
Make sure there's an inch or two of space above the beer line in the bowl, so that the slug has to stretch its neck to get to it. And when they do, they fall in and drown. Take care to clean the traps often and watch for dogs who might also love to lap up some beer!
An organic bait made with iron phosphate might do the trick, as well. One brand that you sprinkle around your plants it called "Sluggo." It attracts slugs, then they eat the bait and die. And note that this organic bait is fairly safe for wildlife and pets, if they happen to get into it, as long as they don't consume too much.
Q: We use a lot of hay to mulch, but we found we have a lot of slugs. We've used Sluggo to keep them under control. Any thoughts about that? - Gary, in Danby
A: In this case, if slugs are still pestering you and your gardens, try building raised beds to plant in. Getting plants and flowers up a bit higher off the ground may deter slugs from getting into your garden.
And if slugs can still access your plants, put some copper stripping around the raised beds and containers. If they touch or climb on it, the slugs will get an electro-chemical shock and turn around.
If you don't have raised beds and are trying to rid your garden of slugs, try using some seashells around your plants as a deterrent. Crush the shells and then sprinkle the shell powder around the plants. Slugs and snails don't like crawling through the sharp pieces.
Q: My perennial flower gardens always look healthy this time of year. After a few weeks though, bugs and slugs and insects find them and they start to eat all the flowers leaves. Should I apply insecticide or fungicide beforehand when the plants are healthy? - Theresa, via email
A: Unless you know precisely what you're spraying for, using an insecticide usually isn't the best plan. There are a couple of cases where you could use a horticultural oil in the winter or early spring, before the leaves come out. That oil can smother any kind of eggs on trees or plants.
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