How to Remove and Prevent Slugs In the Garden

Slugs are a common garden pest found in almost every region of the world, especially in humid climates. They are not insects like other garden pests, such as ground beetles or spider mites, but rather a type of mollusk more closely related to clams.

While some slugs are decomposers, meaning that they feed on dead material, the slugs you’re likely to find in your garden, such as common garden slugs and black slugs, prefer to feed on living plant material. Garden slugs generally feed at night, which can make it difficult for gardeners to identify them as the culprits of plant damage.

Watching for the telltale signs of slug damage on your plants can help you stay on top of the problem. Keep an eye on plants’ leaves, stems, and flowers, as well as the ground, for signs of a slug problem.

• Holes: The leaves or flowers of your garden plants might have small or large holes where the slugs have chewed through them. You might also find these holes in fruits or veggies.
• Ragged edges: Plant stems and leaves might have ragged edges that appear like bite marks.
• Loss of vulnerable plants: Seedlings may be completely eaten, with only their stems remaining.
• Slime trails: Slug slime trails can be seen on leaves, stems, and on the ground or mulch surrounding the plant.
• Slug eggs: Check the underside of leaves for tiny white slug eggs.

Whether you’re worried about slugs visiting your garden in the future, or already have a full-blown slug problem, knowing exactly what attracts slugs can help you take proper preventative measures.

• Wet soil: Slugs need to keep their bodies moist at all times to prevent dehydration, so they love moist soil. If you water frequently so that your soil is constantly damp, or if you have soil that does not drain very well, you’re more likely to attract slugs. Try letting your soil dry out in between waterings.
• Logs and garden stones: Slugs seek out shelter under large objects which offer shade, moisture, and hiding places. Try removing or rotating these objects to deter slugs.
• Dead leaves: Dried leaves can be a great mulch or compost addition, but they’re also a perfect breeding ground for slugs. As piles of dead leaves decompose, they retain moisture, allowing slugs to receive shade and stay hydrated.
• Nutrient-dense plants: Slugs prefer to feed on plants that are high in nutrients and have plenty of large, fleshy foliage, such as marigolds.

Preventing slugs is a lot easier than controlling an active infestation.

• Reduce watering. Slugs prefer wet and damp environments, so you might consider watering your garden less often or watering early in the morning, so the soil has some time to dry.
• Switch to drip irrigation. Drip irrigation is a more efficient way to water plants. With a drip system, you can deliver water directly to plants’ roots, rather than soaking the entire garden, as with overhead irrigation.
• Choose slug-resistant plants. There are some plants that slugs won’t seek out, such as fragrant herbs and plants that have fuzzy leaves. Use these plants to create a strategic border that can protect more vulnerable plants.
• Encourage natural predators. Slugs have many natural predators that will help keep them at bay. Birds, snakes, frogs, beetles, and lizards will all eat slugs in your garden, so consider keeping these critters around.
• Place wool around your garden area. Some gardeners use wool to deter slugs, since they seem to hate climbing over the rough texture. Spread wool around the outside of the garden or around the base of your plants. This method works best for small gardens and flower beds, as larger garden spaces may require too much wool.
• Create a copper barrier. When slugs touch copper, their slime reacts with the metal to deliver an electric shock. You can keep slugs out of your garden by creating a copper fence around using copper tape or copper strips around a garden bed or raised bed, or copper mesh around a larger perimeter.

If you already have a slug problem, there are a few natural ways to get rid of them. Try one or more of these methods for slug control, and remember that getting rid of your garden’s slug population takes persistence.

• Remove slugs by hand. You can pluck the snails out of your garden by hand, although this method might take some time. Drop them into a cup of soapy water to kill them, or relocate them to a location far from your home.
• Create natural slug traps. Slugs will retreat to cool and shady hiding places when the sun is at its peak around noon, so you can lay wooden planks, stones, or even large watermelon rinds in your garden where they will retreat to for shelter. You can then uncover them and find them all gathered in one place, making the removal process easier.
• Set beer-baited traps. Slugs are attracted to the yeast in beer and will seek it out. To make a beer trap, place a shallow dish filled with beer in your garden at night. The slugs will climb in and get stuck. The next morning you can remove the slugs from the beer trap.
• Distribute organic slug bait. Many slug baits use poisons and synthetic chemicals that will do harm to the plants in your garden, and most traditional repellents, insecticides, and pesticides won’t work on slugs. Avoid slug baits that contain metaldehyde or methiocarb and instead choose baits with the active ingredient iron phosphate, which is safer to use around the food crops in your vegetable garden. When using insecticide, always follow package directions.
• Spread diatomaceous earth. Diatomaceous earth is a fine white powder that has microscopic sharp edges that cut the slugs’ skin as they move across it. Unfortunately, the powder loses its strength when it becomes wet, so you will have to use it in areas of the garden where you don’t water frequently and will have to replace it when it rains.
• Sprinkle the slugs with salt. Sprinkling salt over a slug’s body can kill it, although it’s not always as effective as simply removing the slug from your garden. You can use a standard salt shaker or you can create a salt solution with water and use a spray bottle to target individual slugs.
• Lay out sharp-edged materials. Placing sharp-edged organic items in your garden may make it difficult for slugs to navigate the soil. Some gardeners use broken eggshells, dried coffee grounds, cornmeal, or pine needles.

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