Codonopsis tubulosa

Codonopsis tubulosa is a climber that lives for many years. It belongs to the bellflower family, Campanulaceae. Its native range spans the eastern Himalaya to southern China. In China, records list western Guizhou, southwestern Sichuan, and Yunnan. It grows in a mild climate, in alpine scrub and on rocky slopes. It forms tubers below ground and reaches about 5 feet [1.5 metres]. Its stems coil round nearby plants or climb through them. This growth suits garden beds and sunny woodland edges.

Flowers bloom from June to August. Each has both male and female parts for seed growth. Seeds ripen from August to September, after the summer bloom. The supplied species records do not describe flower shape or colour. They give no details of leaves or fruit, either. The RHS lists Codonopsis pilosa as a synonym, another name for this plant. It is not native to Britain or Ireland.

Choose light, rich soil that drains well but stays moist. Sandy soil and loam both suit this plant. It likes soil that is slightly acid but accepts neutral soil. Grow it in part shade or full sun. In full sun, keep soil moist while the plant grows. PFAF lists USDA hardiness zones 6–9. Plants stand cold while at rest, but frost can harm new spring shoots. A site out of early morning sun helps protect them. Do not move plants once their roots have settled in. Their roots do not cope well with such disturbance.

Sow seeds on the compost surface from spring to early summer. PFAF advises acid compost and a greenhouse at this stage. Keep the compost moist while the seeds start to grow. Seeds may sprout within one to six weeks at 20°C. Move each seedling to its own pot when large enough to handle. Keep them under glass through their first winter. Plant out in late spring or early summer. Guard young plants from slugs until they settle in. You can divide plants in spring, with care to avoid root damage.

The roots have a long history of use in Chinese herbal medicine. Growers in China raise this species in place of ginseng. PFAF reports past use for low energy and poor appetite. It also notes that people cook the roots with rice as a tonic. Harvest roots in autumn from plants at least three years old. Yet PFAF gives no edible-use rating and lists no known hazards. These entries do not prove that the plant is safe to eat. Nor do they prove that it has health benefits.