Our weather will be in the 80"s with 5 out of 7 days of rain, rain, strong thunder storms, repeat often . My mini hosta ,I paid good $$$ for from a specialty on line nursery, has gone from sorta mini, to sorta WAY too big for my raised bed. I tried to divide it last year and all the sections I took out died. It looked like the original did too. But this year the orig. is back much bigger than before.
I don't know why the divisions died - I've done this many times before. Maybe its because the raised bed is lite mix, peat moss, vermiculite and perlite and some mushroom compost. The roots free range much more vigorously than when planted in our regular clay junk dirt. I could not dig out enough roots - they had scattered under all the other plants. Oh well!