Return of the Barberry

Credit: John Glover

Once banned in Canada, these remarkable shrubs are making a comeback among B.C. gardeners smitten with their stunning variety of flowers, foliage and fruit

What’s purple, cream and pink and prickly all over? It’s ‘Rose Glow,’ a member of the barberry genus and one of the most colourful foliage plants for west coast gardens. This compact deciduous shrub leafs out each spring in deceptive dark purple, but as spring turns to summer, young leaves begin to add brushstrokes of candy pink and vanilla, sometimes with a little fresh green thrown in for good measure. Think spumone ice cream.

Barberries were banned by Agriculture Canada in 1966, suspected of harbouring a rust disease that could infect cereal crops. Some species are still considered a threat, but fortunately many of the most decorative, especially the Japanese barberries (Berberis thunbergii cultivars), are once again available to B.C. gardeners, and the selection available is increasing yearly.

Tolerant of air pollution and poor soil, barberries will thrive in most situations, as long as their roots get sufficient moisture; in dry summers, it is a good idea to spread some mulch underneath. They have a naturally graceful shape, but also lend themselves well to shearing as a hedge. On the down side, their spines are extremely sharp, which makes them undesirable in close quarters (but great for burglar-proofing a property line), and the brittle stems break easily if the plants are roughly handled. They are a poor choice for siting near deciduous trees, as blowing leaves tend to collect on the lower spines and are difficult to extract without bloodshed.

My young ‘Rose Glow,’ acquired two years ago, grows on the corner of an old shed, where its changing colours play nicely against the weathered barn-red boards. For a more sombre contrast in this dappled shade, I could have chosen B. thunbergii f. atropurpurea whose foliage, claret red in full sun, becomes a dusty blueberry hue so deep that it is almost black in a shadier location. Its arching branches are ornamented with clusters of small yellow flowers in late spring, not very visible from a distance but extremely decorative on close inspection. In fall, droplets of scarlet berries replace the flowers, while the leaves turn to a jewelled mix of red, gold and bronze.

This is a taller, wider plant than ‘Rose Glow,’ growing slowly to a maximum height and width of almost 2 m (6 ft.). Several will make a stunning hedge, and offer burglar protection too, armed with the vicious thorns that all members of the genus conceal behind their pretty leaves.

As a living example of an iron fist in a velvet glove, ‘Royal Cloak’ is a selection with a particularly soft dark texture to its burgundy foliage. ‘Crimson Pygmy,’ also called ‘Atropurpurea Nana,’ is a good choice for a small space, spreading no more than 50 cm (20 in.) high and wide. ‘Gold Ring’ is similar in size and colour, but each leaf is finely edged in gold and the flowers are orange rather than yellow. For a completely different effect, ‘Helmond Pillar’ has, as its name suggests, a narrow, rectangular shape, quite blunt at the top. From a distance it could be mistaken for a dwarf purple Lombardy poplar, and would lend itself to being planted in a row as these poplars often are.

Although purple-leaved forms dominate among Japanese barberries, there are also several golden varieties, most of them quite compact. ‘Aurea Nana,’ whose name means golden dwarf, is a pure-yellow version of ‘Crimson Pygmy.’ It looks its best planted where shade in the hottest part of the day will protect its delicate leaves from singeing. For full sun, ‘Bonanza Gold’ is a tougher selection with leaves of a stronger yellow.

It is easy to be seduced by such exciting colours in foliage plants, and I confess I periodically overdo it in my own garden, to the point that the garden loses its restful ambience. That calls for a return to a good, reliable green such as Berberis thunbergii ‘Tara,’ sometimes sold as ‘Emerald Carousel,’ which has pale-green young foliage, maturing to dark green very finely rimmed with gold. Another option is ‘Kobold,’ a neatly rounded dwarf variety with young leaves as bright as parsley above the mature foliage, and a good crop of shiny scarlet fruits in fall against its reddening foliage.

All of these Japanese barberries have clusters of small spoon-shaped leaves with smooth edges. For a more textural effect, evergreen Berberis julianae has leaves almost as sharply serrated as holly, although they are soft to the touch. Like ‘Kobold,’ new leaves are lime-green, contrasting with the older, darker foliage, but this is a much taller plant: expect an eventual height and width of around 150 cm (5 ft.), slightly taller than wide. Berberis darwinii is another vigorous evergreen variety with three-pointed glossy leaves of dark green. It is also one of the best flowering barberries, loaded with vivid orange flowers in spring. Hailing from Chile, where it was discovered by Charles Darwin during his epic journey on the HMS Beagle, it is less hardy than the Japanese varieties. Slightly hardier and much more compact, evergreen Berberis gladwynensis ‘William Penn’ has leathery leaves and clear-yellow flowers. Its dimensions of only a metre (yard) wide and even less in height have earned it a Garden Clubs of America recommendation for low hedging.

Among cultivars valued more for flowers than foliage, the deciduous Berberis x lologensis ‘Apricot Queen’ weighs down its branches with thick clusters of little bells. From a distance it suits its name, but I think the individual flowers are even more beautiful in close-up, where the apricot dissolves into yellow flushed with rosy pink. Although not quite as eye-catching, Berberis x stenophylla ‘Irwinii’ spaces its pale-yellow flowers more gracefully on arching canes clothed in narrow dark-green leaves. The foliage on both of these shrubs turns red and gold before it falls. Both reach a height of around 180 cm (6 ft.).

Another interesting new B. x stenophylla variety is ‘Pink Pearl,’ which has pink and white thread-like new leaves, pink flowers and narrow sage-green leaves with pale undersides. As it is a recent arrival in local garden centres, I have yet to see a mature specimen, but it promises to be a valuable addition to the pastel palette.

The following plants are hardy to the zone number indicated: Berberis darwinii – zone 7 • B. gladwynensis ‘William Penn’ – zone 6 • B. julianae – zone 6 • B. x lologensis ‘Apricot Queen’ – zone 6 • B. x stenophylla ‘Irwinii’– zone 6 • B. x stenophylla ‘Pink Pearl’ – zone 6 • B. thunbergii cultivars – zone 4

Author and gardener Christine Allen is in demand as a speaker on horticultural topics. Christine’s website is at www.christineallen.ca