Here is some more info from North Carolina Extension that may help you. Peonies grow best in cool climates. Some mail order catalogs provide a rating range from 100 to 300 chilling hours per winter for cultivars. Select cultivars with a low chilling requirement. In general, most of the newer peony cultivars do not perform well in the south because they were bred and selected in northern nurseries and do not receive an adequate amount of cold weather in North Carolina. Many of the older cultivars perform reasonably well in North Carolina including: Baroness Schroeder (white), Felix Crousse (red), Festiva Maxima (white double with a crimson center), Felix Supreme (raspberry), Mons. Jules Elie (medium pink double), Sarah Bernhardt (apple blossom pink), and Teresa (pink).

Site Requirements

Peonies grow best in full sun, but will tolerate light shade. Peonies require winter cold to flower. To encourage flowering, plant on a northern exposure and do not mulch in the winter. Flower size will decrease due to root competition from nearby trees and shrubs. The planting site should have protection from strong winds, but be well aerated to reduce diseases problems. Peonies prefer a well-drained soil with a pH of 6.0 to 7.0. Roots will quickly rot in poorly drained soil; consider planting in a raised bed. Try to avoid locations where peonies have been grown before.