This week, we answer, “How do I stop slugs in my garden?”

What are Slugs?

Slugs are shell-less snails. These slimy creatures are mollusks, vary in size from ¼ inch to 5 inches plus, range from dark black-brown to orange in color, are hermaphroditic, meaning both male and female. In the spring and summer, they lay up to 100 eggs or more. They are highly dependent on moisture in the ground and surrounding habitat. When moving, the slime trails they leave behind become silvery when dry and is used to identify the presence of slugs along with holes in a plant’s foliage.

Where do slugs thrive?

Slugs over-winter as adults hide in the ground. In the summer during the day, they protect from sun and wind underneath things like garden debris, and groundcover, etc. A slug is 80% water, and its slime is 98% water. So, cool, dark, and damp living conditions are essential and the reason they feed at night or during cloudy days. 

Slugs are especially active after rainfalls or irrigation periods. 

What do they eat?

Slugs feed on a variety of living plants as well as decaying plant matter. They have chewing mouthparts and cause plant damage by creating large irregularly shaped holes in leaves with tattered edges. They will eat anything from garbage to bones yet prefer hostas, succulent foliage, flowers, seedlings, herbaceous plants, and fruit. 

How do you control slugs?

There are several ways to help control slug populations. In most cases, a combination of methods works best. 

• Cultural Controls: Eliminate places where slugs can hide, like stones, debris, weeds, and heavy mulches, and try to use plants less susceptible to slug damages. Open up the area to more sunlight and airflow, which slugs do not like. 
• Handpicking: Regularly, pick at night with a flashlight in hand. Water the area before picking to entice the slugs out. 

Creating a Trap

• Trapping: Inverted melon rinds or grapefruit halves make excellent traps. Scrape off the accumulated slugs daily and destroy them. 
• Beer-baited traps work. Use empty tuna cans, place in the ground around plants, and fill with beer (non-alcoholic beer works best). Slugs are attracted to the beer, fall in the can, and drown. As needed, empty and refill with beer.
• Barriers: Copper barriers around beds will keep slugs from entering. Using coarse sand, crushed eggshells or used coffee grounds around desirable plants keep slugs out by creating a border. Sprinkling the soil and or foliage with Diatomaceous Earth acts as a barrier; when slugs crawl across it, they are sliced and dehydrate. 

Go Natural

• Herbs: With mixed results, some herbs have worked as natural slug repellents, including anise, lavender, rue, wormwood, mints, cilantro, tansy, and lemon balm. 
• Handpicking: Regularly, pick at night with a flashlight in hand. Water the area before picking to entice the slugs out. 
• Natural Enemies: Slugs have natural enemies, including ducks, geese, chickens, snakes, toads, turtles, birds, beetles, spiders, ants, harvestmen, and firefly larvae. Invite these guys to your slugfest
• Pine Straw: Using pine straw for mulch seems to deter slug populations. 

Products

• Baits: Slug baits are a consistent method of slug control, but not labeled for edible gardens. Covered containers or bait traps can minimize poisoning concerns. (Cut a 2-liter pop bottle in half and then invert the top part into the bottom portion to create a no escape entryway into this homemade trap. Put your baits inside the container, which now protects it from the kids and wildlife.) 
• Slug Magic is a slug bait, less toxic, and is labeled safe to be used around children, pets, wildlife, the garden, etc. 

*Always read and follow the label/directions on each recommended product before use. Actual slug control will vary due to many factors, and rarely is there ever 100% control. We do not recommend the use of salt in or on top of the soil for slug control.

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