The Paeonia ostii, once included in the P. suffruticosa group, is the most vigorous and fast growing species of all the tree peonies. The Chinese name Feng dan was used to identify the variety of peonies cultivated for medicinal purposes for over two millennia, particularly in the provinces of Anhui, Henan, Hubei, Shaanxi and Sichuan. It grows wild in deciduous forests or thickets on mountain sides at altitudes of over 1,200 m. The single, large flowers, in pure white, are supported by upright and vigorous yet contained shrubs. The species has been dedicated to the Italian botanist Gianlupo Osti who took part in some expeditions to hunt for wild species in China.
