How to Control Slugs in the Garden

Garden slug

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Slugs can be a gardener's nightmare. They hide under leaves in the moist pockets of your garden and will eat almost anything they come into contact with. Slugs are especially damaging to vegetable and berry crops because they eat both the leaves and the fruit. Damage can happen before you even know there's an infestation, but chewed leaves and slimy trails are a tell-tale sign. To rid a garden of these pesky critters, some gardeners turn to homemade solutions, while others rely on commercial treatments. The level of invasion will dictate the methods needed for eradication, as a devastated garden may only bounce back with the use of commercial methods.

When to Control Slugs in Your Garden

Slugs in the garden can be treated at any time during the growing season, however, sometimes it's hard to know they are even there. They camouflage against the brown soil and hide out in damp, dark places during the day. Look for holes and ragged, irregular edges on your lettuce, bean, and cabbage leaves. Strawberries can fall prone to slug damage, too, appearing as if bites were taken out of the fruit. Suspect slugs if you see a slimy secretion on plants, leaves, and the surrounding soil. And when little white eggs appear in the ground, you know it's time to treat.

What You'll Need

Equipment/Tools

  • Gardening gloves
  • Salt
  • Bottle of beer
  • Spray bottle

Materials

  • Diatomaceous earth
  • Organic commercial slug bait
  • Dust mask
  • Granular garden spreader

Instructions

Controlling Slugs Using Salt

Most of the time, slug infestation can be treated with home remedies, as they are fairly easy to trap and kill. And while home gardeners try all sorts of unusual methods to rid their gardens of the slow-moving pests, salt, by far, proves to work best.

Project Metrics

  • Working Time: 1/2 an hour
  • Total Time: overnight
  1. Mix a strong solution of salt and water in a spray bottle. You don't have to be precise, just make sure it's strong.
  2. Wait until nightfall and put on your gardening gloves. Sneak out into your garden and spray the culprits with a stream. The salt solution will dehydrate the slugs within hours.
  3. Come morning, wash any residual salt spray from your plants to prevent damage.

Controlling Slugs Using Beer

Slugs love beer. The sugars contained in the alcoholic beverage reel them in, similar to fruit sugars. Additionally, a glass beer bottle makes a great homemade trap. Slugs can check in, but they never come out.

Project Metrics

  • Working Time: 1/2 an hour
  • Total Time: 2 to 3 days
  • Material Cost: About 5 dollars
  1. Open a few bottles of beer and drink or pour out most of the contents from each bottle. Leave just enough so that you can lay the bottles on their side and the beer won't spill out.
  2. Sneak into your garden during the day and place the bottles in various locations. Lay each bottle on its side and press it into the ground so that the opening lies flush with ground level.
  3. Wait until nightfall and allow the slugs, who are attracted to the beer, to enter the mouth of the bottle. Once inside, they will drown.
  4. Leave the bottles in place for several nights. When they are full of slugs, remove them from the garden, empty them, and discard them in the recycling. Replace with new bottles, if further treatment is needed.

Controlling Slugs Using Diatomaceous Earth

While not every gardener has food-grade diatomaceous earth laying around, some swear by this remedy for anything from ant and bug control to slug eradication. Diatomaceous earth is made of the fossilized remains (silica) of small aquatic organisms called diatoms. This silica is ingested by the critters, causing them to dry up from the inside, yet it is nontoxic to humans and pets.

Project Metrics

  • Working Time: 1/2 an hour
  • Total Time: 2 to 3 days
  • Material Cost: About 10 dollars
  1. Check the weather and wait for a dry day to treat your garden. Make sure there's no rain is in the forecast for at least 24 hours.
  2. Put on your gardening gloves and a dust mask and sprinkle the diatomaceous earth in various spots throughout your garden. Take care not to sprinkle it on the leaves of the plants.
  3. Wait several days for the slugs to ingest the diatomaceous earth and retreat on another dry day, if necessary.

Controlling Slugs Using Organic Slug Bait

Commercial slug control products should be used only for major infestations. Some traditional formulas can be extremely toxic to pets, however organic options (like the ones below) are much safer to use.

Project Metrics

  • Working Time: 1/2 an hour
  • Total Time: 2 to 3 days
  • Material Cost: Under 15 dollars
  1. Purchase a package of Sluggo or Garden Safe slug bait at your local garden center. Both are made of iron phosphate which is toxic to slugs, but nontoxic to humans and pets.
  2. Put on your gardening gloves and check the weather. Make sure to treat on a day that is dry and free of rain, for best results.
  3. Around dusk, fill your garden spreader with the granules and disperse approximately 1/2 to 1 pound per 1,000 square feet around and in between the plants to be protected.
  4. Wait for the slugs to feed on the product at night when they will go underground and die upon consumption.

Tips for Controlling Slugs in Your Garden

In addition to the above methods, you can use birds and animals to naturally control slugs. Backyard chicken farmers can let their birds roam free, eating slugs, bugs, and other pests that accumulate in the garden. You can even train your chickens to eat slugs by tossing slugs inside their run.

Chipmunks also feed on slugs. So if you have them around, leave them alone if they aren't disturbing your garden vegetables.

Copper wire, mesh, ribbon, or tubing is also effective on slugs, as it delivers an electric charge to the creatures. Place it around planters and pots or in perennial beds to control slugs in areas that are rarely disturbed (by digging or harvesting) during the growing season.