kousa said:You need to plant the plants as deep as possible, burying the grafted tap root below 3-4 inches below soil line so that they do not send up growths which can take over the tree peony.
I know. I have lots of grafted plants(grafted some myself), and i usually just prune away the wild growth. And there might be a chance that i want to have one that's not cultivated, so if a wild branch emerges i will let it grow for one season, and then slowly separate it from the mother.