Controlling

Snails and slugs

in your garden

Controlling

snails and slugs

In Your Garden

Controlling

Snails and Slugs

In Your Garden

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CONTROL SNAILS IN YOUR GARDEN WITH THESE ECO-FRIENDLY PRODUCTS

Copper barrier

Corry’s Slug and Snail Copper Tape Barrier

Horticultural fabric (row cover)

Easy Gardener Plant and Seed Blanket

Baits containing iron phosphate

Bayer Advanced Natria Snail & Slug Killer Bait, Bonide Slug Magic, Escar-Go!, Lilly Miller Worry Free, Miracle-Gro Nature’s Care Slug and Snail Control, Monterey Sluggo, Natural Guard by Ferti-lome Slug & Snail Bait

While Californians treat snails as pests, our pesky garden mollusks were actually imported from France during the Gold Rush—for French restaurants in San Francisco. Unfortunately, a few escaped… and the rest is horticultural and agricultural history. Snails and slugs are closely related. They both have soft, oblong bodies and produce quantities of slime to help them move around. The most obvious difference is that snails have shells.

WHAT'S EATING YOUR PLANTS?

Are your vegetable and flower seedlings being devoured overnight? Are you finding large ragged holes in your prized ornamentals? Do slime trails cross your walkways? If so, your garden is probably harboring snails and/or slugs.

Snails and slugs are active mostly at night and on dark, cloudy days. On sunny days they can be found in moist, shady spots. If potted plants are being eaten, look for eggs and young snails around the inside edges of the pots, and find slugs under pots. Eggs resemble small pearls and are laid in masses of up to 100. When you find eggs, crush them or scoop them into a plastic bag, seal it, and put the bag in the garbage.

LESS-TOXIC CONTROLS

Once snails or slugs invade your garden, it may take time to keep their numbers down. Try two or more of the following control strategies.

Hand-pick snails and slugs at night

  • To be effective, hand-picking must be done thoroughly and regularly. Collect nightly until it’s hard to find snails and slugs, then check once a week.
  • During dry weather, the best time for hand-picking is before dawn or after 10 or 11pm when snails and slugs come out to feed. Use a flashlight and gloves or tongs. You can check earlier, but you won’t find as many. On damp days they may be out earlier.
  • Crush snails and slugs completely or drown them in a pail of soapy water (they survive in plain water).

Protect plants with barriers

Before using barriers, pick snails and slugs by hand for a few nights.

  • Wrap a strip of copper tape around a tree trunk, flower pot, or the sides of wooden garden beds or fences. Snails and slugs are repelled by the unpleasant reaction between their bodies and the copper.
Row cover use dto keep pests out of growing plants in the garden
Row covers keep snails out
  • Cover seedlings with small cages made from plastic or galvanized metal window screen. Push the cages into the soil so snails and slugs can’t squeeze under. Check to make sure that no snails or slugs are caught inside the cage.
  • Cover rows of vegetables with special horticultural fabric that lets in light and water but excludes snails and slugs.

Hand-pick snails and slugs at night

  • To be effective, hand-picking must be done thoroughly and regularly. Collect nightly until it’s hard to find snails and slugs, then check once a week.
  • During dry weather, the best time for hand-picking is before dawn or after 10 or 11pm when snails and slugs come out to feed. Use a flashlight and gloves or tongs. You can check earlier, but you won’t find as many. On damp days they may be out earlier.
  • Crush snails and slugs completely or drown them in a pail of soapy water (they survive in plain water).

Protect plants with barriers

Before using barriers, pick snails and slugs by hand for a few nights.

  • Wrap a strip of copper tape around a tree trunk, flower pot, or the sides of wooden garden beds or fences. Snails and slugs are repelled by the unpleasant reaction between their bodies and the copper.
  • Cover seedlings with small cages made from plastic or galvanized metal window screen. Push the cages into the soil so snails and slugs can’t squeeze under. Check to make sure that no snails or slugs are caught inside the cage.
  • Cover rows of vegetables with special horticultural fabric that lets in light and water but excludes snails and slugs.
Row cover use dto keep pests out of growing plants in the garden
Row covers keep snails out

Trap slugs and snails

  • You can trap snails and slugs under upside-down flower pots, dark-colored plastic sheeting, and wooden boards. Place these traps around the garden and collect snails and slugs in early morning.
  • Homemade or commercial traps that use beer or yeast mixtures to lure snails and slugs to death by drowning and/or intoxication may help, but hand-picking will probably still be necessary.

Encourage natural predators

Many species of ground beetles kill snails and slugs. Most of these beetles are large (1 to 2 inches), black, tank-like creatures. They are found in the same moist habitats as their prey: under rocks, boards, leaves, etc. Avoid killing these helpful bugs.

Use iron phosphate bait

  • Iron phosphate baits are less toxic than other formulations. After eating iron phosphate, snails and slugs stop feeding and die within three to six days. They often crawl into secluded places, so you may not see dead bodies.
  • Reapply iron phosphate baits every two weeks if needed.
  • Keep iron phosphate baits and all other pesticides out of the reach of children and pets.
  • Read the label before you buy a snail bait product. Avoid baits containing methiocarb, which kills earthworms and beneficial insects. Baits containing metaldehyde are more toxic than iron phosphate baits, and metaldehyde is very toxic to dogs.

PREVENTION

  • Snails and slugs are attracted to large areas of ivy, nasturtiums, and succulent ground covers. They also hide in clumps of agapanthus, lilies, daffodils, alstromeria, and iris. They are less attracted to plants with dry, hard leaves like rhododendrons, junipers, and bamboo. Regularly search their preferred plants for snails and slugs when you’re hand-picking.
  • Moisture makes any area much more attractive to snails and slugs. Avoid over-watering and use drip emitters to deliver water only where it is needed. Water early in the day to allow the area to dry out before nightfall. You may need to remove mulch from areas with severe slug or snail problems.
  • Remove any boards and flower pots that you aren’t using as traps.

WHAT TO DO WITH CRUSHED, DEAD SNAILS?

Leave a few dead snail and slug bodies on the soil surface to attract more snails and slugs and make your collecting easier. (Large piles will breed flies.) Or, bury crushed mollusks three or four inches underground to add nutrients to the soil and avoid fly problems.