What are slugs and what do they do? – Slugs are simply 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 (male and female) laying up to 100 eggs or more (spring and summer), and are highly dependent on moisture in the ground and surrounding habitat. The slime trails they leave behind (when moving) become silvery when dry, and is used to identify the presence of slugs (along with holes in the plant’s foliage!). Slugs over-winter as adults, hiding in the ground. In the summer, they hide during the day under garden debris, mulch, rocks, boards, weeds and groundcover, to stay out of the sun and wind. A slug is 80% water, and its slime is 98% water, so cool, dark and damp living conditions are important, and the main reason they feed at night, or during cloudy days. Slugs are especially active after rainfalls or irrigation periods. Slugs (snails) 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 prefer succulent foliage or flowers, seedlings, herbaceous plants, and fruit lying on or close to the ground, etc., but eat anything from garbage to feeding on bones. Hosta are definitely one of their favorite plants!
How can I control Slugs in my garden? – There are several ways to help control slug populations, and 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 areas to more sunlight and airflow, which slugs do not like. Handpicking: Have a ‘Slugfest’ to see who can pick the most slugs. Pick at night with a flashlight in hand. This is effective if done on a regular basis. Water the area before picking to entice the slugs out. Trapping: Inverted melon rinds or grapefruit halves make excellent traps. Scrape off the accumulated slugs daily and destroy them. Beer-baited traps work nicely. 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. Empty and refill with beer as needed. Barriers: Copper barriers around beds will keep slugs from entering. Using coarse sand, crushed egg shells, or used coffee grounds around desirable plants creates a border to help keep slugs out. Sprinkling the soil and or foliage with Diatomaceous Earth acts as a barrier; when slugs crawl across it, they are sliced and dehydrate. Even using pine straw for mulch seems to deter slug populations. And although results can be mixed, some herbs have worked as natural slug repellents, including anise, lavender, rue, wormwood, mints, cilantro, tansy, and lemon balm. Baits: Slug baits are probably the most consistent method of slug control, but not all are labeled for around edibles. Covered containers or bait traps can be used to minimize poisoning concerns. (Cut a 2 liter pop bottle in half and then invert the top part into the bottom part 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.) Bonide’s Slug Magic or Espoma’s Slug & Snail Control are all natural based slug baits, less toxic / much safer, and can be used around children, pets, wildlife, the garden, etc. 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! *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. [Resources include OSU Extension Service]