Clematis 'Kaiu'

Clematis 'Kaiu' was raised in 1982 by Estonian breeder Erich Pranno and named after his home village of Kaiu. Clematis viorna is recorded as the seed parent. The nodding, initially urn-shaped flowers are tinted pale pink when young and turn pure white with age, while the tips of the four sepals curl attractively outward as the flower becomes bell-shaped; creamy stamens shimmer inside. At around 3 cm across, the individual flowers stay dainty but appear in great numbers.

'Kaiu' displays its abundant flowers from June to September. Reaching up to 400 cm, it is one of the more vigorous members of the viorna group and is well suited to tall trellises and climbing frames or as a companion for larger shrubs, into which it happily climbs. It thrives in sun to semi-shade regardless of aspect – 'Kaiu' is robust and undemanding, tolerating even drier, alkaline soils well.

'Kaiu' is reliably winter-hardy (zone 6, down to about -23 °C). Since the flowers appear on the current year's growth, cut the plant back hard to about 25 cm in March – this encourages dense, floriferous new growth. Wear gloves when pruning, as the sap may irritate the skin.