Depending on your location slugs and snails can be the bane of the gardener’s life. You know this must be true when you come across books with titles like “50 Ways to Kill a Slug”. While many of the remedies mentioned in that book are intended to be humorous rather than practical, the fact that a book could be written on the topic indicates the extent of the problem. I found an article by Tony Leland over on Dave’s Garden website which reviews the four main ways to battle these pests.

On an early morning stroll through the garden, sipping a mug of steaming coffee and inhaling the fresh dewy air, one comes upon a new begonia bloom with most of the petals chewed off. What a way to start the day! One or two slugs in a flower bed can wreak havoc, so prepare yourself for the onslaught of this night visitor.
These “snails without shells” have been around for centuries and, according to horticultural references from the late nineteenth century, have plagued mankind’s gardens worldwide, especially in areas of high humidity.1 Slug damage not only affects the aesthetics of the garden, but the holes in (or defoliation of) a plant or fruit also provide a gateway for disease, not to mention relegating the specimen to an “un-saleable condition.” The bad news is that “land slugs” – those we battle in our gardens – are hermaphrodites (having both female and male reproductive organs). Yes, every slug you see (or not) lays eggs!
Okay, enough about the history and love-life of these pests. What can you do about them?
The first and best control method consists of reducing the conditions for favorable habitat. Moist, cool, protected sites will attract slugs seeking shelter during the day and conditions in which to lay their eggs. Look at your gardens and determine ways to open them up to more sun or warm air. Over-mulching can provide perfect conditions for slug residence, so be sure mulch is 2 inches or less; keep the mulch material away from plant stems and trunks – an excellent hiding place with easy access to food. Remove dead or dying leaves from large-leaved plants such as Hosta or Caladium; this decaying material left in the garden provides yet another place to hide.

See more at Dave’s Garden