Guest Author - Nikki Phipps

The 30 to 40 species of the genus Codonopsis are relatives of Campanula and native to the mountains of Central Asia, Korea, and Japan. They are perennial herbs that grow from thick tubers (resembling a radish). Some species have long thin stems that twine through low shrubs or climb over rocks, while others form low, sprawling shrubs. The flowers vary from star-shaped to bell-shaped and their colors range from white, cream, and light green to blue, maroon, and black or a combination of these colors. While their blooms have beautiful, brightly colored patterns inside, most species have a rather unpleasant smell emanating from their foliage.

Since most are climbers, Codonopsis are best planted at the bases of small shrubs. When planted among shrubs the plants will happily meander about, decorating them with flowers. Codonopsis is also a choice plant for a well-drained sunny or semi-shaded border, rockery, or wall. Although Codonopsis prefers to be located in partial shade, it will thrive in areas of full sun if the roots remain cool. Most species are hardy, and all require a moist but well-drained soil. In regions having wet winters, a sheltered position with dry mulch is recommended. Growth usually begins in late spring. Codonopsis can be easily grown from seed or its tubers; however, the tubers may take several years to reach flowering size. Generally, once established Codonopsis are best left undisturbed.

The Asian Bellflower (C. clematidea) sprawls rather than climbs. This species has large, pale-blue, nodding bell-shaped flowers with a beautiful orange and maroon pattern inside. It blooms in summer, reaching a height of around 2-3 feet. C. clematidea is excellent for rockeries, path edging, and containers. Another beautiful species is C. forrestii. This one is a gently twining species, with wide, pale-blue star-shaped flowers. C. pilosula is another climber, with lots of green bell-shaped flowers, occasionally having purple markings on the outside. This species is usually found growing along stream banks or under the shade of trees in its natural habitat. The plant is shrubby and dense enjoying adequate summer moisture in well-drained soil. Another stunning species is C. grey-wilsonii with beautiful blue, star-shaped flowers. The leaves are rich green and heart-shaped. This species is a scrambler, rather than a climber, reaching heights of up to 3 feet. The spectacular large-cupped variety of this species (C. grey-wilsonii 'Himal Snow') has pure white flowers.

Most of these species are also known as Poor Man’s Ginseng as the tubers are used for medicinal purposes, such as energy deficiency, lack of appetite, strengthening the immune system, and lowering blood pressure. However, Codonopsis looks sensational simply as a garden plant.