Family:	Ranunculaceae
Genus:	Clematis
Cultivar:	‘Bill MacKenzie’
Height:	8m
Spread:	4m
RHS AGM

Cultivar raised by Valerie Finnis (UK), hybrid of C. orientalis (S Europe to W China) x C. tangutica (NW Asia).

Genus name is derived from the Greek for ‘vine-branch’. Cultivar is named for W.G.MacKenzie, who was curator of the Chelsea Physic Garden and mentor to the breeder.

A deciduous climber grown for its unusual yellow lantern-like flowers in summer. Climbs to 8m, with a spread of 4m. Hardiness H6

Leaves are mid-green and hastate with irregularly-serrated margins.

In July to October, bears open bell-like flowers 6-7cm across. A circle of red-brown stamen are surrounded by four thick yellow sepals, leading to another common name of ‘lemon peel clematis’. Flowers are followed by silky seed-heads which last throughout the winter.

Stems are thin and wiry, both new shoots and petioles twine around supports to enable the plant to climb.

Should be planted with the crown around 6cm below the surface, to encourage new shoots. Like most clematis, the ideal is to have its head in the sun, and its feet in the shade; in a sunny position roots can be shaded with rocks or ground-cover plants.

Prefers an alkaline or neutral soil and needs good drainage. Tolerant of poor, sandy soil.

Can be pruned right back to around 30cm in spring, or left to go on its own merry way.

May be troubled by aphids and earwigs, and clematis slime flux may be a problem.

Propagate by layering in spring or autumn, or by semi-ripe cuttings in summer.

A vigorous scrambler, best used to drape itself along a hedge or climb its way up a tree. Vigorous enough to form a hedge in its own right, and could be aided in its mission by a late-flowering honeysuckle (eg Lonicera periclymenum ‘Serotina’), which is just as vigorous, enjoys the same conditions and has complementary flowers. Can also be grown within bounds, given an annual pruning.