What makes Clematis 'Bill MacKenzie' worth cultivating is the fact that it remains attractive until late autumn and winter, adding interest to the garden. It's a vigorous vine using petioles (leaf stalks) to wrap around the supports.
Clematis Tangutica Group ‘Bill MacKenzie’ photo Sz. Marczyński |
Szczepan Marczyński
Clematis 'Bill MacKenzie' has ability to quickly cover tall fences, arbours or unsightly buildings. It grows up to 6-7 m and branches rapidly, but it's less rampant than Fallopia aubertii. The list of its virtues is quite extensive, with beautiful yellow flowers, silky seed heads, green leaves lasting well into early November, long flowering period, and low site requirements, as just some of the most prominent ones. Clematis 'Bill MacKenzie' has fairly large, 6-7 cm across, bell-shaped nodding flowers with thick textured dark yellow sepals and a tuft of crimson-brown stamens.
Its bloom time starts around mid-June and ends with the first frosts (5oC below zero) at the beginning of November. In summer, after the first crop of flowers, silky seed heads start to form beside newly opened blossoms, gleaming in the sun and giving the plant a fluffy appearance. Towards the end of October the plant gets even more conspicuous - most of the neighbours' foliage is gone or, at best, has turned to yellow or brown whereas Clematis 'Bill MacKenzie' still boasts beautiful flowers and green leaves. During the winter withered leaves and seed heads, covered with hoar frost and snow, create a spectacular display.
Clematis Tangutica Group ‘Last Dance’ (Orange Peel) - photo Sz. Marczyński |
It starts late in spring, and it's only around mid-April that its growth begins. Though slow in the beginning, it quickens toward flowering time, and in May the plant rapidly sends up shoots up to 4-5 m, so if the support is low (e.g. a fence 180-200 cm tall), the cultivar should be pruned in summer in order to prevent it from growing beyond whatever is supporting it, and becoming unsightly.
Clematis 'Bill MacKenzie' thrives best in sunny or lightly shaded locations. It's fully hardy and quite undemanding, tolerates well dry poor soil, but will perform badly in dense and soppy one, so good drainage is essential. No special pruning is needed, but you can cut it back hard if you need to keep it in bounds. From a practical point of view this is best done somewhere around the end of March and the beginning of April, and the plant should be cut 10-30 cm from the ground.
It makes a great subject for a very effective screen, suitable for growing over tall fences, arbours, pergolas, or even scaling trees.
Clematis Tangutica Group ‘Bill MacKenzie’ photo Sz. Marczyński |
One of its close relatives from the Tangutica Group which can be used in a similar way is Clematis 'Orange Peel', which has recently been renamed 'Last Dance' on account of its late bloom time. It has small (4-5 cm across) intensely yellow flowers with exceptionally thick sepals that turn to orange-yellow after the first autumn chills.
It flowering season starts in July-August but lasts well into mid-November. It's a less vigorous grower than Clematis 'Bill Mackenzie', reaching 3-5 m, has smaller green-blue leaves and is less free-flowering.