This tree peony was grafted onto a herbaceous peony root stock. I did not know this when I bought it. Apparently, it is a common practice that allows the tree peony root to get a healthy start. Once the tree peony is established, the herbaceous root is supposed to die. Well, in this case, the herbaceous peony was out growing the tree peony. At any rate, this year I pulled out all shoots from the herbaceous root. This seems to have worked. I am much smarter now:)
