I'm going to amend this fall right after Labor Day. Our first frost is not until late October to early November. I may be sorry but the plants on my hillside didn't do well last winter, lost so many. Soil is good for 6 inches then heavy soil. I new that but, was hopping the hill would be enough to move the water. The hillside is also faced with a rockery which would add to free flowing water one would think. Oh well live and learn.
This has been an interesting summer for us, unusually hot and dry. Nothing like you Lyn, but many days in the 90's. Early Spring is better to divide and move, after last frost date. Early spring is just too busy for me.