Posted: 25/02/2014 at 15:37
I think you are totally wasting your time with Egg shells. As soon as the shells, however ground up they are, get wet then Slugs just glide over it. Tried, been there and never again.
You are better to try small grit and sand as I have found Slugs do not like going over that...unless the plant gets with reach and they use that to climb over to the plant.
In summer I go out at night to pick up slugs - put salt in the water in a bucket and the slugs die quickly. I avoid using blue pellets but sometimes it is the only thing to cull the population.