Slugs and Snails
Pest · Commonly affects: Lettuce and other leafy greens, Strawberries, Tomatoes, Basil and tender herbs, Beans, Hostas and ornamental seedlings
Slugs and snails are soft-bodied mollusks, not insects, that feed on a wide range of garden plants and thrive in cool, damp, shaded conditions. Gardeners care because they can shred seedlings overnight and disfigure leafy crops and ripening fruit, doing most of their damage while you sleep.
How to identify it
Both are slimy and gray to brown or tan, with snails carrying a coiled shell and slugs having none; adults range from less than half an inch to several inches long. The clearest sign is not the animal but its trail: irregular holes with smooth edges chewed into leaves and the silvery, dried slime tracks they leave across foliage, mulch, and hardscape. Because they hide by day, you often confirm them by scouting after dark with a flashlight or by looking under pots, boards, and dense leaves.
Damage
They rasp ragged holes and notches in leaves, stems, flowers, and low-hanging fruit, and can clip off young seedlings and transplants at the soil line before the plants ever establish. Feeding wounds also open the door to soft rots and other decay organisms, so lettuce heads, strawberries, and ripening tomatoes may spoil where they have been chewed.
Prevention
Keep the garden less inviting by watering in the early morning so the soil surface dries by evening, and by giving plants wider spacing and good airflow to reduce the damp, shaded canopy they favor. Practice sanitation: clear boards, bricks, weeds, and heavy decaying mulch that serve as daytime hideouts, and pull spent lower leaves off leafy crops. Rotating where you plant susceptible crops and starting with vigorous, well-hardened transplants helps young plants outgrow the stage when they are most vulnerable.
How to manage it
Handpick them after dark or on cloudy, wet mornings and drop them into a bucket of soapy water, and set out simple traps such as inverted flower pots, melon rinds, or wooden boards that you flip over and clear each day. Ring vulnerable seedlings with barriers of coarse, scratchy material like crushed eggshells or copper edging, and keep a bare, dry strip between mulch and stems so the moist bridge to the plant is broken. Encourage natural predators such as ground beetles, birds, toads, and garter snakes by leaving some habitat and avoiding broad insect controls, and remove any chewed, rotting tissue promptly to keep secondary decay from spreading.
General guidance for US home gardens, focused on prevention and non-chemical control. For a confirmed diagnosis and options specific to your area, contact your local Cooperative Extension office. Page updated Aug 4, 2026.