Botanical name: Paeonia lactiflora
Common name: White peony root
Literal name translation: white peony
Family: Ranunculaceae, buttercup family
Part used in Chinese medicine: root
Major Chinese medicine actions:
Nourishes Liver blood, regulates menstruation, calms Liver yang,
alleviates pain, preserves the yin
Photo 1: Paeonia lactiflora; 05/2008; author C. Micleu; permission Jade Institute
Photo 2: Paeonia lactiflora; 05/2008; author C. Micleu; permission Jade Institute
Photo 3: Paeonia lactiflora; 05/2008; author C. Micleu; permission Jade Institute
Peony lactiflora is native to northern China, Mongolia, and eastern Siberia. Differing from the "tree peony", these plants are herbaceous, dying to the ground completely in winter. Cultivated as ornamentals since about 900 B.C., there are hundred of varieties grown today, ranging from double to single petals and in a wide range of colors and shapes. Originally, only the single flowering forms were used in Chinese medicine, and as with the tree peonies, those with yellowish flowers were considered the most rare and valuable. At present, the roots of all species of P. lactiflora may be used for the medicinal herb Bai Shao.
In Chinese medicine, Bai Shao, or "white peony" is actually the root, with root bark removed, of the cultivated Paeonia lactiflora plant having any colored flower. Chi Shao, or "red peony", is the root with root bark intact, of the wild-harvested Paeonia lactiflora or Paeonia veitchii, also of any colored flower. Pictured here are Bai Shao cultivar varieties, "Mrs. FDR" (pink), "Topeka Garnet" (red), and "Bowl of Cream (white).
Growing and Propagation
Peonies are herbaceous perennials commonly grown for their large, showy, sometimes fragrant flowers, blooming in late spring to early summer. They prefer full sun or partial shade conditions, and soil that is deep, fertile, humus-rich and moist, though well drained. They benefit from being protected from strong winds. The plant is hardy in USDA zones 3 to 8.
Propagation is best by division, but plants may also be grown from seed. Seeds should be planted in containers outdoors in autumn, but generally can take two to three years to germinate. Plants may be divided in early fall with root pieces that are at least 2 inches long. When re-planting the roots, the new growths, or "eyes", should be planted 2 inches below the soil level. They require careful transplanting, trimming secondary and tertiary roots, and special care and fertilizing, to successfully grow young plants from division.
Harvesting and Preparation
For medicinal purposes, peony roots are harvested in August through October, after 4 to 5 years of growth. The roots are cleaned and washed, and for the herb Bai Shao, the bark of the root is removed. In order to remove the root bark, roots are boiled in water until the interior cross section is no longer white, or until sticky and fragrant, then immediately immersed in cold water. The root bark is then easily removed by scraping with a bamboo knife or broken piece of porcelain. A metal instrument is not used for this procedure as it tends to easily damage and bruise the roots. An alternate simple method is to scrape off the root bark right after harvesting, and then boil the root for 5 to 15 minutes until the interior is soft. After either method, the roots are dried in the sun before cutting into slices.
The interior of the root must be thoroughly dry, and in traditional practice, the roots are stacked in pyramid-shaped piles and allowed to "sweat" for a day, then spread out to dry in the sun again. This process of stacking and sun drying may be repeated several times. The roots are later sliced by the herb distributors, first re-hydrating them in water until each is uniformly damp and flexible. Slicing is done by hand and then they are again dried in the sun.
Good quality roots are white or slightly pinkish in color, depending on the depth to which the skin was removed. They should be solid and heavy, without clefts or hollow parts. For the herb Chi Shao, the bark is left on the root, resulting in slices that are reddish brown on the outside with a pale red or yellowish white cross-section.