Copper tape barrier for slugs and snails

Copper tape creates an effective perimeter barrier around raised beds that deters slugs and snails. When a slug's moist body contacts copper, it triggers a mild electric-like reaction caused by a chemical interaction between the copper and the slug's mucus, causing discomfort that makes the slug turn back. Apply a continuous strip of adhesive-backed copper tape (at least 2-3 inches wide for best results) around the exterior of the bed walls, approximately 2-4 inches above ground level. Ensure there are no gaps at seams or corners where slugs could bypass the barrier. Clean the tape surface periodically with vinegar to remove oxidation that diminishes effectiveness, especially in humid or coastal climates. Copper tape costs $10-20 per 30-foot roll (brands: Slug Shield, Copper Barrier Tape). Wider tape (3+ inches) works better than narrow strips because slugs cannot bridge their bodies across it. This method is most effective as part of a multi-pronged approach combined with iron phosphate bait, beer traps, or handpicking. Reapply annually or when tape shows significant oxidation.