I am in zone 3a and I was very nervous when planted peony divisions in the fall the first time. They made it and showed up next spring. Our soil usually freezes in late September. Unfortunately the springs became very long (at least the last 2 springs) so the soil where my peony grew thawed only in mid May, very late. # of my newly planted roots hardly made it and now the plants are still tiny. We'll see if they show up next spring because I am afraid there is too little time to grow feeding roots and save energy in the storage roots. Zone 3a does not mean long winters, the conditions can be much more friendly for peonies in other 3a zone areas.