Fighting slugs in the garden is not fun. It really irks to watch your vegetables that you worked to grow being devoured by them. Green the fun times has a nice list of ways to control them. I have tried the eggshells without much success.
I keep eggshells in my garden begs already, they break down and provide calcium to the soil and they attract birds ( I think they eat them to make their own eggshells stronger) but they also eat bugs while they forage on the shells so its a win win situation. What they don’t do is deter slugs.
I use the diatomaceous earth for other pests so I think I will try putting it around the base of plants this year and see if it will deter the slugs.
9 All Natural Ways to Keep Slugs Out Of Your Garden