Large, flat, purple-blue flowers with a wide, pale reddish-purple bar; outside purple-blue with a pale yellow bar. The flower becomes pale purple with age and the bar becomes narrower. Filaments pale greenish yellow; connectives and anthers dark red, pollen pale creamy yellow. Seed-heads persistent.

"When this clematis first flowers the centre is a greenish yellow colour, and the bars are bold and approximately blue. The bars and sepals change slowly from purple to light purple. As a result of these processes, the sepals present almost seven colours of the rainbow."