A There are a few ways to stop slugs eating your hostas. You can surround them with a ring of crushed eggshells, which are too sharp for the slugs to crawl over.
You can bury beer traps too. Fill some small containers with beer and bury them in the soil, so they are level with the surface. Slugs are attracted to the smell, and crawl in and drown.
Most gardeners swear by going out in the garden in the evening, just after it gets dark, with a flashlight. Pick off all the slugs you can find and dispose of them.
The best way to keep hostas safe is to employ more than one of these methods.
Unfortunately, the damp spring we had this year meant that slug populations have been really strong this year. Let’s hope for a cold winter that will kill them off!
Hope this information helps you, and good luck.