Snails are considered pests by many gardeners since they can damage or even destroy plants. For an effective, natural way to repel snails and prevent them from ruining your garden, erect some barriers that snails won't cross.
Snails move by gliding along a trail of mucus secreted by their foot muscle. They feed on both living and decaying plant material, injuring them by chewing holes into leaves, fruit and bark. They often destroy young seedlings in the process. Picking snails from your yard by hand is one chemical-free way to remove them, but it can be hard to find them since they usually come out at night.
Copper barriers are a natural repellent for snails. Thin sheets of copper placed around pots and tree trunks prevent snails from climbing up. Snails do not like to touch copper, apparently because the copper reacts with the snail's slime trail and creates an electrical shock. Strips of copper nailed along the sides of raised garden beds will prevent snails from making their way inside. If possible, bury the bottom of the copper strips into the ground 1 to 2 inches to prevent the snail from digging underneath the barrier.
Dry Line Repellents
Dry lines of naturally abrasive material such as sawdust, ashes and diatomaceous earth act as barriers to prevent snails from migrating into protected areas. Snails don't like to cross these lines but the repellents are only effective if they stay dry. These barrier lines should be about 1 inch high and 3 inches wide to discourage the snails from attempting to cross.