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Growing Your Own Growing Your Own Vegetables | Composting | Container Gardens | Fall/Winter Gardens | Fertilizing | Insect Pests | Plant Diseases | Planting Guidelines | Raised Beds | Regional Tips | Site Selection | Slugs | Soil Improvement | Tilling | Warm-season Crops | Watering | Weeds Protect Your Plants from Dreaded Slugs  Hand picking  Barriers and traps  Nontoxic control products  Chemical control products Slugs thrive west of the Cascades. Damaged plants are marked by slime trails and irregularly shaped holes with smooth edges. The amount of slug damage depends mainly on rainfall and nighttime temperatures. Slugs must have soil moisture, and they feed when temperatures are greater than 50°F. They love mild winters, wet springs, moist summers, and irrigation. Cold, windy winters and hot, dry summers reduce their numbers and cause some slugs to become dormant. Grass cover, mulches, soil cracks, and worm tunnels provide places for slugs to hide and lay eggs. Remove dark, moist habitats and rototill to a depth of 6 inches to eliminate these hiding places. Slugs lay eggs in the fall after rains start, typically in late September and early October. If you reduce the population before they lay eggs, you have won half the battle. Hand picking Hand pick slugs about 2 hours after sunset. Slice them in half, pierce them, sprinkle them with salt, or scrape them into a bucket of soapy water. Enlarge photo Slugs are attracted to the odor of beer and will drown in a beer-filled trap. You can purchase traps or make your own from yogurt containers. Barriers and traps Copper strips. When a slug touches copper, it is charged with current, an unpleasant experience that makes it reverse course. Place a band of copper (preferably 3 inches wide) around beds or individual plants. Or form copper wire into a tight, conical spiral around each plant, with the small end at the bottom, and push the wire into the soil. Make sure slugs are not trapped inside barriers. Trap boards. Slugs seek shelter during daylight. Place small, flat boards under plants and between garden rows. Remove slugs each morning and scrape them into a bucket of soapy water. Beer traps. Slugs are attracted to yeasty odors. To make a beer trap, cut a 2-inch hole about two-thirds up the side of an empty margarine tub or plastic yogurt container. Bury the container so the hole is just above ground. Add 2-3 inches of beer (or a mixture of 1 tablespoon (Tbl) yeast, 1 Tbl flour, 1 Tbl sugar, and 1 cup water) and cover with a lid. Remove dead slugs daily. Trap crops. Slugs love to eat marigolds. Plant marigolds along your garden's border and hand pick slugs and dispose of them in late evening. Nontoxic control products Iron phosphate granules (e.g., Sluggo, WorryFree, and Escar-Go). These granules have a wheat aroma to attract slugs. After eating them, slugs stop feeding, dry out, and die within 3 to 6 days. Bait remains active for about 1 week or longer depending on the environment. Diatomaceous earth. Made of ground mineral fossils, this powder punctures slugs' soft covering. Sprinkle it in a 1-inch-deep, 3-inch-wide band around a plant's base. Rain can destroy its effectiveness, so you may have to reapply it. Chemical control products Ammonia-water spray. When sprayed directly with a solution of equal parts household ammonia and water, slugs dehydrate. Test a plant's sensitivity to ammonia by spraying a small section and watching for a reaction in the next day or two. Metaldehyde. Metaldehyde is the most common active ingredient in synthetic chemical baits. Use these baits in the fall. By late winter and early spring, conditions are too wet and slugs can recover. These baits are toxic to earthworms and may affect nontarget insects. However, it's possible to use them safely. Place a few pellets under a board and remove dead slugs each morning. Or, place granules in a 1-gallon plastic milk container. Make a 1-inch by 2-inch hole in the side of the container near the top and bury the container so the hole is above ground.

Produced and distributed in furtherance of the Acts of Congress of May 8 and June 30, 1914. Extension work is a cooperative program of Oregon State University, the U.S. Department of Agriculture, and Oregon counties. Oregon State University Extension Service offers educational programs, activities, and materials without discrimination based on age, color, disability, gender identity or expression, marital status, national origin, race, religion, sex, sexual orientation, or veteran's status. Oregon State University Extension Service is an Equal Opportunity Employer. Copyright © 1995- Oregon State University. Disclaimer.