A Tree Peony by William Gratwick before 1960. Data relating to itsparents is restricted to the presence of rockii in its genes. It is a spreading, vigorous shrub with large flowers. It has been noted that on first flowering the flowers were much lighter than those that followed in later years. The images alongside show the later,more charcateristric flowers which tally with other images on theweb.Plant Source: Binnys.