Answer: There are lots of ways to foil slugs, and I suggest using a combination of tactics. You can make life hard for them by removing leaf litter or other mulch from the soil surface and spreading a thin layer of sand or crushed egg shells on the ground instead. This will do away with their daytime hiding places and create a rough crawling surface which they should avoid. Spreading a layer of diatomaceous earth around the base of your plants can help, too, the sharp particles slice open their tender bellies. Or, many gardening catalogs carry copper slug barrier tape (Gardener's Supply Co. 1-800-863-1700; Garden's Alive 1-812-537-8650). If slugs attempt to scale it they'll sizzle to death. One other bit of trivia for you, the variety of hosta 'Sum & Substance' is highly slug resistant if you ever want to give it a shot!
I have heard about the ammonia and water mixture to keep slugs off hostas, but I've never heard of the mixture used on other plants. I think I'd try barriers and traps first, before shooting new little plants with ammonia and water.
For a complete history of slugs, their likes and dislikes, and other control tactics, visit the following website:
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