dig them and pot them up in anticipation of a move? it would cause me tear to have to leave these.
This is the time to dig peonies. Depending on how long before you move you can either pot or bag with barely damp peat or other material. You only want it slightly damp. If more than feel damp to touch you could rot your roots.
So which brand of soil is best if you transplant a tree peony into a container?
maifluer, thank you kindly for your advice. they will stay potted for several months.
I have found peony to be very accepting of transplanting. I once dug a perrenial peony up with a backhoe in the middle of winter without knowing what it was and stuck all the tubers in a metal pail to take home just for kicks. It filled with water and froze solid. In the spring I ended up with two dozen peony growing straight out of the rusty water. I put them in the ground and now have two dozen nicely blooming double pink peony. I imagine you'll show more love than my backhoe so fret not.