How can I get rid of the slugs that are eating my plants?
Slugs feed at night and on damp, cloudy days. By keeping the area around your foundation clean and free of debris, you can help to eliminate their hiding places. You can hand pick them and dispose of them in a pail of soapy water (a rather unpleasant task). Or, they will drown in shallow containers filled with beer, sunk into the ground with the lip at ground level. These containers will need to be emptied each day. Barriers, such as diatomaceous earth or crushed eggshells, can be placed around your plants as well. These materials work by piercing the bodies of slugs and other pests, causing desiccation. Cautionary note: beneficial insects are also vulnerable, so use diatomaceous earth only around specific problem areas.
Courtesy of the NYBG Plant Information Service