Hi Jay

I'm not sure if it is possible to kill a rose of sharon, but I would not hesitate to move them now. Just make sure they have regular water up until freezing, and check to make sure they don't heave with the thaw/freeze cycles.

I think now is a great time to transplant. I just moved a fairly sizeable gold thread juniper, witch hazel and nandina. The juniper and nandina didn't even wilt a bit but the witch hazel seems a bit dry at least the flower buds seem a bit wilted. I also transplanted a gold arborvitae and small japanese maples with no transplant shock. The moist cold weather is less damaging than the hot drying summer sun. Just be sure to keep them watered well...as if you need to do that with all this rain.