Slugs and Snails

Slugs and snails feed on a variety of plants leaving ragged, irregular shaped holes in the leaves or devouring entire seedlings. Plants with soft, succulent leaves, like hosta, lettuce, peppers, marigolds, and dahlias, are their favorites. If there are ragged holes in your annuals, perennials, or vegetables, but you see no insects, slugs and snails have likely been dining in your garden. Slugs devour foliage, while snails eat decaying organic matter. In the Washington area, slugs are generally a greater problem than snails.
Slugs and snails emerge from winter resting-places to begin feeding in the spring. They lay egg masses repeatedly through the warm months. The eggs hatch in four weeks and mature in several months. Slugs and snails need cool, moist conditions to survive. They typically spend the daylight hours hiding under leaves, rocks, and sticks, waiting for cool wet evenings when they come out and feed. Slugs and snails may feed during the daytime on cool, overcast days.

CONTROL

Many methods of controlling slugs and snails have been tried with varying degrees of success. Early intervention, in April or May, will help reduce the population for the months to come. The first step is to remove excess leaf litter, boards or other hiding places.

TRAPS

Place cabbage leaves, grapefruit rinds, or boards in the garden to provide a place for slugs and snails to hide. Check these traps each morning and destroy the slugs. Concern makes an excellent trap called "The Pit" which works quite well.

BARRIERS

Put copper tape around flowerpots or specimen plants. Slugs and snails will not crawl over the copper. Sprinkle Concern diatomaceous earth, wood ash or crushed eggshells on the surface of soil or mulch. These materials are abrasive and irritating. They must be reapplied after rainfall. Concern also makes a product called Slug Stop which works as a barrier.

DETERRENTS

Rosemary plants deter slugs and snails. Decollate snails are natural predators for garden snails. Merrifield carries decollate snails seasonally or can order them for you.

PESTICIDES

Pelletized, granular and liquid baits are available to attract and kill slugs and snails. They are convenient and effective. They need to be reapplied every two weeks. Do not use these products around children, dogs, cats, or other wildlife that may be attracted to the bait and accidentally poisoned. Apply to the soil, not the plants. Always read and follow label directions when using pesticides. Products include Bug-Geta, Bug Geta Plus, Deadline, and Sluggo.