Slugs Are Active Year-Round
Many gardeners assume slugs disappear in winter, but several species remain active in temperatures above 40 degrees F. They feed on cool-season crops like lettuce, spinach, and kale, often causing more damage per plant than summer pests because fewer plants are available.
Identify Slug Damage
Slug damage appears as irregular holes with smooth edges, often with a silvery slime trail nearby. They prefer tender new growth and can skeletonize young seedlings overnight. Check plants early morning with a flashlight for the best chance of spotting them.
Physical Barriers That Work
Sharp materials deter slugs because their soft bodies are easily injured. Spread diatomaceous earth, crushed eggshells, or wood ash around vulnerable plants. These barriers need reapplication after rain. Copper tape around raised beds creates an electric shock effect that slugs avoid.
Beer Traps: The Classic Method
Sink shallow containers into the soil so the rim is level with the ground. Fill with cheap beer or a yeast-sugar-water mixture. Slugs are attracted to the fermentation odor, fall in, and drown. Place traps 3-5 feet apart and check daily.
Encourage Natural Predators
Ground beetles, birds, toads, and hedgehogs all eat slugs. Provide habitat with log piles, stone walls, and shallow water dishes. Avoid pesticides that kill beneficial insects, as this removes natural slug control and creates worse outbreaks.
Remove Hiding Places
Slugs hide under boards, pots, debris, and dense ground cover during the day. Clean up garden debris, elevate pots on feet, and keep the area around raised beds clear. Reducing shelter forces slugs into the open where predators find them.
Iron Phosphate Baits
For severe infestations, iron phosphate baits (Sluggo, Escar-Go) are OMRI-listed and safe for pets and wildlife. Slugs stop feeding after consuming the bait and die within days. Apply around the perimeter of garden beds and reapply after heavy rain.
