I received 20 dormant peony cuttings. I'm in zone 5 and the ground is still
frozen/muddy.

Oh, dear. The prope time to plant peonies is September. Keep them in a garage
so they will stay dormant until your soil is workable. Then heel them in in a
growin bed as soon as possible. Plant them properly in the fall. Or ask your
extension agent about the best practice in your area.
Iris,
Central NY, Zone 5a, Sunset Zone 40
"If we see light at the end of the tunnel, It's the light of the oncoming
train."
Robert Lowell (1917-1977)