As the nights turn cool, and the soil is still warm, it's an ideal time to plant.
Planting in the fall, when the soil temperature is at 40F or above, allows for good root development before the onset of winter. Peonies, fruit trees and berry bushes planted this fall will take off growing next spring. We at Cricket Hill Garden are shipping peonies and fruit trees to USDA zones 4 and 5. USDA 6, 7, 8 & 9 will follow as the weather cools.
This video shows you how to properly plant a tree peony. A properly sited tree peony will reliably bloom every spring for decades.