The hosta garden...

Lovely Hosta's, how do you combat the slugs ?

I'm not sure, this year we've been really lucky & havn't had any damage from slugs or snails, we have a lot of frogs in the garden so maybe this is something to do with it, or maybe it's that this border is mulched with slate & I know snails & slugs tend to avoid climbing over anything rough & gravelly so maybe the slate is the answer...??