Clematis 'Hakuōkan'

syn: C. 'Haku Ookan'
Family: Ranunculaceae
Pronounced: KLEM-uh-tiss

 

Quick Jumps

Growing Guide
Rainy Side Notes

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GROWING GUIDE

Origin:
Garden.
Plant group:
Vines.
Hardiness:
Sunset zones: All.
USDA zones: 4-9.
Heat zones: 8-1.
Mature size:
Height: 6-8 feet (1.8-2.4 m).
Flowering period:
First flush of flowers in the spring, and second flush in late summer to early fall.
Flowering attributes:
Deep, rich, royal purple, single flowers consisting of seven to eight pointed tepals with creamy white stamens. Semi-double flowers sometimes occur.
Leaf attributes:
Deciduous, green leaves.
Growth habit:
Climbing.
Light:
Full sun to partial shade.
Soil:
Fertile, humus rich, well-drained soil.
Feeding:
Mulch well with composted manure or compost. Fertilize once a month with a complete organic fertilizer during the growing season.
Propagation methods:
Layer branches in late winter.
Basal and softwood cuttings in spring.
Division in spring.
Semi-ripe cuttings in early summer.
Pruning methods:
Pruning group 2 or B.

 

Rainy Side Notes

This clematis blooms in front of my living room window in its full glory in May. Stunning when smothered in enormous purple flowers, I planted it underneath my rose of Sharon shrub—Althaea 'Collie Mullens'. The moss and lichen laden branches of althaea is holding up to the onslaught of royal purple blossoms beautifully. Unfortunately, when the shrub flowers later it’s almost a letdown after the vine’s spring extravaganza.

This clematis can be grown on a number of shrubs or small trees. I wouldn’t mind seeing it twining and flowering through my Viburnum tinus ‘Variegatum’. The vine is suitable for growing in containers too.

I’ve noticed there are several spellings of its name—‘Haku Ookan’, ‘Hakuookan’, ‘Hakuokan’, ‘Haku Okan’, ‘Haku-okan’ and ‘Hakuōkan’. I used the last spelling, as this appears in several trusted resources. The RHS Horticultural Database lists ‘Hakuokan’ as an accepted name. Translated from Japanese, it means "white royal crown" and refers to the striking creamy white stamens.

Back in 1957, Yashio Kuboto raised this vine of unknown parentage in Japan, and Jim Fisk introduced it to the UK in 1971. True to its name Clematis ‘Hakuōkan' now rules over my spring garden.

Photographed in author's garden.