Snails and slugs are small, soft-bodied animals that can be troublesome pests in the garden. They are very similar to each other, except snails have hard shells and slugs do not. They can cause serious damage in the garden and often remain unseen since they feed at night or on rainy days. During the day, they can be found hiding in damp places such as in thick groundcovers or under flower pots. The most characteristic signs of their presence are the trails of mucus they leave wherever they crawl.
Type of Damage
Snails and slugs feed on both decaying and living plant material. Parts of plants that can be affected include leaves, stems, and below-ground parts. They produce large, ragged holes and can completely consume young seedlings.
A very wide variety of plant materials can be affected, and they are especially troublesome on hostas, strawberries, lettuce, basil, and cabbage.
Snail and slug damage begins in the spring and continues to occur until the first frost. These pests are particularly found in wet, damp areas since moisture is required for their survival. During drought conditions, their activity decreases.
Controls
Discourage snails and slugs by removing mulch and leaf litter near plants. When found, these pests can be removed by handpicking or by making simple, effective traps. Trap snails and slugs in shallow pans of stale beer sunken so that the lip of the container is even with the soil surface. Replace beer as necessary when it dries up or becomes diluted by rainfall. A pie pan suspended with nails over the pan of beer will help to keep out rain, as well as dogs and cats.
Snails and slugs can also be attracted with pieces of potato or cabbage placed underneath a board and then collected and destroyed during the day. Protect young seedlings by sprinkling diatomaceous earth around the plants. Diatomaceous earth is very sharp and scratches the skin of these soft-bodied critters, resulting in dehydration and death. It must be reapplied after rain or watering.
Pesticide baits are also effective for controlling snails and slugs but should only be used as a last resort. Products containing mesurol should NOT be used in the home garden. Products containing metaldehyde bait can be used to control snails and slugs around certain fruits and vegetables in the home garden. However, many newer products now contain iron phosphate, which is a much safer option for most fruit and vegetable plants in the garden. Examples of available iron phosphate baits are:
- Bonide Slug Magic Pellets – Makes Slugs Disappear
- Garden Safe Slug & Snail Bait
- Monterey Sluggo – Kills Slugs & Snails
- Natural Guard Brand by ferti-lome Slug & Snail Bait
- Whitney Farms Slug & Snail Killer 1
- Natural Guard Bug, Slug & Snail Bait (also contains spinosad)
- Bonide Bug & Slug Killer (also contains spinosad)
- Gardens Alive Garden Pest Bait – Insect, Slug & Snail Bait (also contains spinosad)
- Monterey Sluggo Plus (also contains spinosad)
Iron phosphate will stop feeding by the snails and slugs quickly, and it is much less harmful to pets, birds, and non-target insects than metaldehyde. Any unconsumed iron phosphate bait adds nutrients (iron and phosphorus) to the soil. Consult the label for application rates and the specific crops it can be used around. Spinosad is a natural insecticide that in baits will also kill cutworms, ants, and earwigs.
Additional slug & slug control products:
- Monterey All Natural Snail & Slug Spray RTU (contains rosemary oil, clove oil, & cottonseed oil)
- Earth Pure & Natural Final Stop Snail & Slug Killer Spray (contains rosemary oil, sesame oil, peppermint oil, thyme oil, cinnamon oil, and garlic oil).
Pesticides are updated annually. Last updates were done on 11/24 by N. Jordan Franklin.
Originally published 05/99