If you have access to scrap copper, it can help to reduce the slug damage in the garden. Create a circle of copper pipe or wire to surround each plant. The electrolytes in the slime on the slug's body react with the copper to cause an electrical charge, causing the slugs to seek food elsewhere. If the slugs return, clean the copper with vinegar to reduce the tarnish buildup, which renders it ineffective. Others encourage slugs to seek greener pastures using sandpaper, diatomaceous earth or eggshells on top of the ground.
Add plants in your garden that deter the activity of slugs. Rosemary, anise and fennel are just a few choices. Disperse these plants around those known to attract slugs, such as strawberries and tomatoes, to protect the crops.
Use methods to reduce the slug population and protect the garden at large. Traps built with shallow containers buried at ground level and filled with beer can be used to capture and drown slugs. Black plastic or boards placed on the ground provide a hiding place for slugs. Turn them over in the morning and then kill the slugs with salt.