I would suggest putting a ring of roof shingles or rough sandpaper around the base of your plant. It will cut them if they try to cross it and then they will dry up. The ring should have a radius of at least three inches.

I don't like using chemicals, so I use beer. Use a small container about an inch deep and put beer in it. I just use a cover off an instant coffee jar or cut the bottoms off plastic containers. Yogurt or whatever. They love it and will drown themselves in it. Stale beer is fine. The stuff I am using is 2 years old. I just store it with my garden stuff in a bottle so it won't evaporate.

Thanks for giving me some suggestions. Really appriciated. I might try rough sandpaper as I don't drink at all :)