Non-Toxic Ways to Keep Slugs and Snails Out of Your Garden

You may not see them often, but slugs and snails have a way of making their presence known. Eating up to six times their weight in plant material per night, these troublesome mollusks can leave your hostas (and other plants) looking like they’ve been raked by machine gun fire.

Although they’re most active in the evening, you can combat these pests any time of day with these strategies. Some methods are benign, simply dissuading slugs and snails from bothering your plants. Others may seem more extreme, but gardeners who value their plants won’t object even to those measures.

1. Beer Bash. Bury tuna fish cans or plastic yogurt cups up to their rims, then crack a beer and fill the cups (the older and more stale the beer, the better). Slugs and snails will be attracted to the yeasty aroma, fall in and drown. Replace the beer as needed.
2. Find an Edge. Sprinkle sharp sand, crushed eggshells or diatomaceous earth (the fossilized remains of tiny aquatic organisms) around plants. The slimy creatures won’t want to cross over the sharp material to get to their buffet. Bonus: Diatomaceous earth is harmless to birds, bees and mammals and provides trace elements to the soil.
3. Ashes to Ashes. Slugs and snails also avoid wood ashes because of their alkalinity, so you can distribute wood ashes from the fireplace (but not from charcoal, which may contain chemicals) in the garden. Over time, ashes can increase the pH of the soil, so use sparingly.
4. Band Together. Although not cost effective for a large number of plants, copper bands can be placed around prized plants that are vulnerable to attack. When slugs slither across the copper band, the moisture in their slimy trail sets off an electrical current (similar to an electric shock) and keeps the pests from continuing their journey.
5. Set the Bait. Iron-phosphate baits are considered safe for wildlife but deadly for slugs and snails. According to Oregon State University Extension, iron-phosphate baits are just as effective as metaldehyde baits, but not toxic to pets and wildlife. The mollusks eat the bait, cease feeding and die within a few days. Some brand names include Sluggo and Garden Safe Slug & Snail Bait.
6. Search and Destroy. Use a flashlight to hunt for snails and slugs in the evening, about two hours after sunset. (If hunting during the day, look in shady, damp areas and beneath leaves and other garden debris.) When you find a slug or snail, shake some salt on it — a deadly ingredient that dehydrates the pest. Or pick it up and place in a jar of soapy water.
7. Attract and Kill. You can also set a trap by placing boards in shady areas of the garden where slugs and snails hide in the daytime. Lift up the boards, scrape off the pests and destroy. An alternate idea is to place inverted grapefruit rinds in problem areas of the garden. Turn them over in the morning, scrape out and destroy.