Codonopsis Convolvulacea

Delicate-looking, pale blue to violet (sometimes white) flowers, which can be up to 5cm across, open in mid-summer on this deciduous climber, which is happy to scramble through shrubs and woody plants in the mixed border. It originates from the Himalayas, China, Sichuan and Yunnan, where it grows in open places and woodland margins at 2000-4000m.