How to Control Slugs and Snails

Adult slugs can range in size from a half inch to 10 inches.

Slugs are found throughout North America, particularly in moist, temperate climates. Snails require calcium for their shells, so are less common in areas where this mineral is lacking. Slugs are gray to black or brown (even orange!) and soft-bodied, often with soft hump in center; snails have a hard calcium shell. Both snails and slugs feast on most plants, especially young, tender transplants, leafy vegetables and succulent plant parts. Their presence is indicated by large, irregularly shaped holes in the leaves of plants and shiny slime trails. They are active mostly at night and in wet weather. Slugs and snails are very prolific; individuals of some species lay up to 500 eggs per year.

Controls

Slug Magic pellets contain the active ingredient iron phosphate, a naturally occurring mineral. Once slugs ingest it, they stop eating and die within a few days.

Reduce the number of daytime hiding places in the garden. This includes the undersides of boards or buckets, mounds of moist garden debris, etc.
Use a slug trap or fill shallow containers with beer and sink them into the soil to trap slugs and snails.
Damp soil and stagnant air are ideal breeding conditions for slugs. Keep plants thinned out and promote good air circulation.
Handpick and destroy slugs and snails as you encounter them—you can capture more by "hunting" at night.
Create a barrier of diatomaceous earth, crushed eggshells or lime around susceptible plants.
Lure slugs away from your garden (distract them) with treats, such as hollowed-out grapefruit halves or old lettuce leaves.
Choose slug-resistant plants. In general, slugs dislike anything with leaves that are glossy, waxy or hairy. They also seem to avoid plants with strong-smelling foliage, such as rosemary, marigolds and lavender.
Avoid creating pockets for slugs to hide and lay eggs. Before filling new pots with soil, cover the drainage hole with a small piece of fabric.
Water in the morning instead of the evening so foliage is dry overnight.
Surround susceptible plants with copper barrier strips—they give slugs a slight shock on contact.
Encourage predators, which include birds (blackbirds, robins, crows, ducks and geese), frogs and toads.

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