The peony, Paeonia, is a long-lived perennial or shrub of Eurasia bearing large, full, many-petalled flowers. Its name comes from Paeon, the physician of the Greek gods, and a myth explains it: Paeon used the plant to heal a wound, and when his teacher Asclepius grew jealous, the gods saved Paeon from death by turning him into the flower that bears his name. The plant thus carried from the first a reputation as a herb of healing and protection, and its seeds and roots were worn as amulets against harm, folklore recorded here as history.
A specific legend explains why Luoyang, rather than the imperial capital, became China's peony city: the story holds that the empress Wu Zetian, ruling in the seventh century, ordered all the flowers in her garden to bloom in the depth of winter, and when the peonies alone refused, she had them banished in punishment to Luoyang, where they flourished so magnificently that the city's association with the flower has outlasted the empress by well over a thousand years, a tale illustrating the flower's long-standing reputation for a certain proud independence. The peony most bound up with Chinese luxury, the tree peony, Paeonia suffruticosa, is a woody shrub, botanically and horticulturally distinct from the herbaceous peony, Paeonia lactiflora, the softer-stemmed perennial more familiar in Western gardens, though both share the name and much of the symbolism recorded here.