Tree peonies that originally come from China have some of the most imaginative names. This one was, presumably, named after Yang Guifei a famous Chinese concubine of Emperor Xuanzong of Tang. Known as one of the great beauties of China, she was also reputed to have been found of her alcoholic refreshments . As I heard the story, it was given that name because the gracefully flowing petals were reminiscent of the concubine's robes flying around her as she ran through the palace in disarray.
Chinese producers of tree peonies however are well known for being rather careless about keeping track of the names of seedlings so I have seen pictures of several very different looking flowers all of which claim the same name.
