Clematis 'Blue Light'

Clematis 'Blue Light' was raised in 1998 by Dutch breeder Frans van Haasterd of Boskoop as a sport of the well-known cultivar 'Mrs Cholmondeley', and is registered under the cultivar name 'Vanso'. Its 10–12 cm flowers glow in vivid violet-blue: on the early growth they are usually double to semi-double, while later in the season they tend to appear single, with six sepals, fine blue veins and creamy-yellow stamens.

At up to 300 cm, 'Blue Light' suits trellises, arches and other supports well and grows more compactly than many other large-flowered hybrids – a larger container on a balcony or terrace also works. It flowers from June to September, with a first flush on last year's wood in early summer and a second flush towards the end of summer. In a sunny to semi-shaded spot with shaded roots – for example under low neighbouring plants or a layer of mulch – it thrives in almost any aspect.

'Blue Light' is reliably winter-hardy (zone 6, down to about -23 °C). After the first flowering, cut the plant back to about 100 cm in June; in early spring it is enough to remove dead and weak shoots. Give it one to two years to establish after planting before it reaches its full flowering power.