There's much to be said for foliage and it seldom gets the recognition it deserves. It can be likened to the setting for a play - in view of the audience (you, the gardener) during the entire production (i.e. the growing season), while the actors (aka, flowers) come and go. It's especially appreciated at the beginning and end of our prairie season when flowers have yet to appear or have been killed by a hard frost. If the foliage is any colour other than green, it acts as an accent season long.
One species of hardy shrubs, the Japanese barberry (Berberis thunbergii), provides outstanding foliage during the Prairie summer, mostly in shades of purple and gold. Among the cultivars are both small and large shrubs, fitting into both smaller urban landscapes and more expansive rural spaces.
It's called "barb" berry for a reason: the sharp, needle-like spines along the stems mean that it's lovely to look at but decidedly not huggable. Native to Japan, these shrubs are dense, rounded and multi-stemmed. Most of the cultivars range in height from 0.6-1.8 metres and are grown primarily for their colourful foliage, generally yellow or pink and purple. The leaves are deciduous on the Prairies. The small yellow flowers are inconspicuous and usually hidden by the foliage. The bright red berries sometimes persist through the winter.
The unimproved species is rarely available but there are several cultivars. Among those with purplish foliage that are smaller and more suitable to an urban landscape are:
Burgundy Carousel only 0.6 metres in height with a one-metre spread, has purple summer foliage, becoming deep purple in fall.
Ruby Carousel, one metre in height and spread, has reddish-purple foliage in summer and fall.
Concorde, a dwarf at only 0.6 metres in height, with a spread of one metre, is slow growing and deep red purple.
Rose Glow, one metre in height and spread, is a 1957 Dutch introduction, with mottled rose pink foliage in spring, becoming deep purple by fall.
Royal Burgund is dwarf, 0.6 metre in height and spread, with burgundy foliage in summer, turning deeper burgundy in fall.
Larger purple leafed barberries, more useful in rural settings, include:
Cherry Bomb is 1.2 metres in height and spread and deep crimson all season with an open, branching form.
Royal Cloak is one of the larger cultivars (1.2-2.4 metres in height and spread), upright and arching with dark reddish-purple foliage.
Note: dark purple on its own can become lost in the shadows, disappearing into a black hole. It is best placed slightly in front of and to the side of a shrub with gold, yellow, silver or variegated foliage. Or plant in front of a light coloured fence, house or other structure.
Two of the barberries have golden-yellow foliage:
Golden Nugge is compact and mounded with lovely golden-orange foliage in spring. It is 30 to 60 centimetres in height and spread. New spring growth is golden with orange tones, becoming golden during summer and orange pink in fall.
Sunsation is larger, vase-shaped and more upright, reaching 1.2 metres in height and spread. It is yellow in summer with golden hues in fall.
Jade Carousel, one of the few green cultivars, reaches one metre in height with a spread of 1.2 metres; 'Emerald Carousel, also green, is similar but slightly larger (one to 1.6 metres tall and wide). Foliage of both turns red in fall.
Place barberries in full sun or light shade in well-drained soil. They are very drought-tolerant once established (after one or two seasons). They may die back if exposed to very cold temperatures in late fall or early winter without an insulating snow cover. The purple types seem more susceptible, but often recover by midsummer. Barberries are useful in a mixed or shrub border, rock garden, a mass planting or an informal, untrimmed hedge.
Next week: More shrubs with purple and gold foliage.
Williams is the author of the new and revised Creating the Prairie Xeriscape. In her latest book, 'Saskatoon Forestry Farm Park & Zoo: A Photographic History,' she tells of the history of an institution and the personal stories of the people who made an important impact on Prairie agriculture.
- This column is provided courtesy of the Saskatchewan Perennial Society (www.saskperennial.ca; [email protected]). Check out our Bulletin Board or Calendar for upcoming horticulture events: fall bulb sales; garden information sessions.
