Lawn and Garden Shop
Garden Improvement Information Series

Garden Slug & Snail Control Notes

On this page we have provided information for the home gardener for dealing with slugs and snails in our gardens. This short fact sheet article was written to give you a good source of information on controlling slugs and snails and reducing the damage that they inflict upon our vegetable and flower gardens.

No one method of slug control will provide the results that we need. Therefore a combination of strategies must be employed. The four ways that we can recommend are hand picking, baiting, trapping, and building barriers. Usually a combination of two or more strategies is best.

For a better understanding of the object of our concerns so that we can better deal with these little creatures, we have linked to these websites. These information guides covers land snails and slug species that presently live in the Pacific Northwest, their habitations, habits, and other facts.
Identification Guide to Land Snails and Slugs of Western Washington Click Here .

HAND PICKING:
This time honored method of pest control includes picking up and removing the slugs and snails from the garden. The best time for finding the slugs and snails is early morning, evening, and after dark using a flashlight. It seems that each gardener has their perfered method of collecting these unwanted members of the Gastropoda class of mollusks. Our method is to use a plastic vegetable bag from the supermarket. We put our picking hand in the bag and then collect the slug and snails and place then in a tin can. Look under large leaves, on the plants and under cool hiding places where they are resting or sleeping.
Disposal is easy, especially if you have ducks or chickens. They love them.
Hand picking also includes finding and removing slug eggs from the garden. Slugs lay 30 to 100 round pearly eggs in a cluster or mass. Each egg measures approximately 1/16 inch in diameter. These egg clusters can be found under rocks, in shallow protected holes in the soil, and under garden mulch and debris. Slugs lay their eggs during the entire growing season and their eggs usually weather over winter just fine.
One great advantages to hand picking is that once you remove each slug or snail and their eggs, they are gone for good, with no harm to any other critters in your garden. The big disavantage is that it is time consuming.

SLUG BAIT:
Slug baits are usually effective and you do not have to spend much time. Be especially careful when choosing chemical slug baits. Read the label, some contain metaldehyde, a nerve poison that can seriously harm or even kill pets. If you do decide to use this type, read and follow the label carefully. And place the bait where the slugs can get at it but not your small childern or pets.
We do no use metaldehyde based baits in our gardens because we do not know much harm they do to earthworms. And we use lots of earthworms in our gardens.
Some of the newer chemical baits do not contain metaldehyde, but the acive ingredient is iron phosphate. The iron specifically is poison to slugs and snails. And these baits are not highly toxic to your pets or to birds.
The iron/phosphate baits work best when scattered lightly near and among the plants that need protection. Rain stations are not required. Rain breaks these baits down into iron and phosphate. While both of these elements are generally useful fertilizer, these baits are not intended to be a fertilizer.
And as with all chemicals and pesticides, read and understand the labels. Remember to keep all chemicals and pesticides away from childern.
And another downside is cleaning up the dead slugs and snails.

TRAPPING:
Some gardeners rely on stale beer traps. These trap are simple to make and will work. Select a protected area where the slugs will frequent. Fill a shallow flat pan with beer. Place the pan in the ground with the rim extending about 3/4 inches above the ground. Raising the rim above ground level will help to prevent benefical insects like predatory ground beetles from falling in. The traps work by drowing the slugs after they crawl in and drink the beer.
Downside: Usually not enough slugs are attracted to the beer traps. And if the pan isn't protected from the rain or sprinklers, the water will wash all the beer out.
Advantage: Works great with most slugs populations, but should be used with other methods also.
Another useful trapping method is to lay black plastic, boards or overturned planting pots on the ground in a place where the slugs and snails may seek shelter from the drying heat of the sun. Almost anything that provides shelter and is cool and damp will attract them. Check under these traps each early morning and late afternoon and hand pick them for prompt disposal.

SLUG BARRIERS:
Slug and snail barriers is our most perferred method of slug and snail control, with hand picking a close second. Well placed barriers work day and night 24 hours every day. However, first lets clear up some somewhat misleading information that we all read about in some gardening magazines. Wood ashes, eggshells, diatomaceous earth and other similiar ideas, while they may work in other parts of the world, wouldn't provide much help in our cool, damp, and sometimes continually wet spring and late fall gardens. This is because most of these methods rely upon dryness to effect their usefullness.
One barrier useful during the dry summer months, is a strip of bare loose very dry soil about three to four feet wide around the garden or between the garden and the source of your slugs and snails (vacant lots or deep forest). But this strip must remain very dry, always. The wet edge away from the garden, is a good place to place the chemical baits. And to watch for those few slugs and snails heading out for your garden and hand pick them.
Copper slug barriers have been used in the wet Pacific Northwest with good results. A strip of bare copper sheeting nailed or stapled to a raised bed will work, provided that no vegetation dangles over the copper strip to provide a way over the copper strip for the slugs or snails. These barriers must be a minimum of three inches wide.
These strips can usually be obtained at nurseries. But be sure to obtain wide enough strips or double then up.
Advantages: Properly built and maintained barriers work 24 hours each day.
Disadvantages: Cost of buying and installing can be somewhat costly.

Animal Kingdom helpers:
Important helpers around our farm when it comes to controlling slugs, are our fleet of domestic ducks. And not to lose out, are some of our chickens. We turn the ducks loose to hunt slugs in the areas around the fenced vegetable garden and some of the flower beds. Also they do a great job in the fruit and nut orchards, as well as the berry gardens. These ducks were "trained" when they were young to leave everthing else alone, but the slugs and bugs. And they generally follow the rules. They learned at an early age that slugs were great to eat.
Advantages: Willing and able helpers
Disadvantages: Not many, just keep watch on the ducks in some areas. Especially the berry gardens when the berries are getting ripe!

NOTE! We do NOT use any harmful chemicals or commercial slug, snail or bug bait to kill or to control slugs, snails, or bugs. This is important to keep in mind if you should decide to allow your ducks and chickens to hunt and devour your slugs, snails, and bugs.

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This website page was first published February 24, 2002.

This page was last updated February 24, 2018.