By Mary Yee, contributor

China is the original home of most of the peonies grown in the world.  The most commonly grown type is the herbaceous Paeonia lactiflora, a very hardy perennial that dies to the ground each fall.  P. lactiflora features diverse flower forms and colors, and thousands of varieties have been selected by gardeners over centuries of cultivation.

However, China is also the home of the tree peony.  It has woody stems that form a permanent framework of branches and, over time, develops into a large shrub or small tree.  It is the tree peony that the Chinese call “Hwa Wang” or King of Flowers.  The general name for tree peonies in Chinese is “mudan (牡丹).”  

Both kinds of peonies, herbaceous and woody, were first cultivated by the Chinese for the medicinal properties of their roots.  Peonies are still widely planted in China today for medicinal production.  But the beauty of peony flowers ensured that the plants soon made their way into gardens and into Chinese art.

Chinese peonies were introduced to the west in the 18th century although the botanical riches of China, including additional peonies species, continued to be explored and documented by scientists through the 20th century.  In 1926, Dr. Joseph Rock (1884-1962), a plant explorer for the Arnold Arboretum of Harvard University, came across a white-flowered tree peony in the courtyard of a Buddhist monastery in western China.  The monastery, called the Choni Lamasery, was located at an elevation of over 8000 feet in the southwestern part of Gansu Province.  Rock was able to collect seeds from this plant and the Arnold Arboretum distributed the seeds to botanical gardens around the world.  The first flowering from these seeds occurred in 1938 at various locations and the beauty of the flower created a sensation in western horticultural circles.

The flowers are very large, white petalled, with golden stamens that are beautifully set off by the distinctive dark purple flares at the base of the petals.  The plant itself is robust and long-lived, becoming a large shrub over time.  In fact, one of the plants grown from Rock’s original seed collection may still be growing in Highdown, the Sussex garden estate of Sir Frederick Stern, a noted English horticulturalist who published a monograph on peonies in 1946.