One really effective method for repelling slugs (which isn't covered on this website) is the use of caffeine.
A study in Christchurch, New Zealand has discovered that high concentrations of caffeine kill slugs and snails, and low concentrations repells them.
Instead of putting my coffee grounds into the compost I spread them straight onto the earth around my slug prone
plants. When i have a large crop that needs protecting i get extra grounds from cafes.
This works so well that my
plants are never touched by slugs and snails, as long as i keep applying my morning coffee scraps to the beds. My spinach is a particularly deep green as well, as it thrives on the high nitrogen content of coffee. If you need a cheap, quick fix(!), instant coffee can be made up at the concentration you would drink it and sprayed liberally over
plants in danger, however, this only lasts until the next rain.
Hope somebody finds this useful.
xxoo janet.