Prickly but pretty, barberry is making a comeback, Gillian Vine says.
A fascinating aspect of gardening is how many weedy plants have acceptable relatives, cultivated varieties that are worthy of any garden.
A few that come to mind are montbretia (Crocosmia), elderberry, rose and ranunculus.
Then there is barberry (Berberis). Two species, the common barberry (B. laucocarpa) and evergreen Darwin’s barberry (B. darwinii) are now considered invasive weeds.
Introduced in 1916, B. glaucocarpa comes from the Himalayas, while Darwin’s barberry is from Chile, arriving here in 1946. The vicious spines made these two popular as hedging, as was the deciduous European barberry (B. vulgaris), still common around old Central Otago properties.
There are about 450 barberry species — widespread in temperature regions, although New Zealand has none of is own — and hundreds of cultivars. These are mainly derived from two deciduous species, B. vulgaris and the Japanese barberry (B. thunbergii), both of which have fine autumn foliage colour. The purple version of the latter (B. thunbergii f. atropurpurea) has reddish-purple leaves in spring and summer, which turn orange-red in autumn. Birds like the red berries.
The beauty of these newer varieties is the size and colour range, from evergreen golden barberry (Berberis x stenophylla) at 2.5m-3m tall, deciduous red Helmond’s Pillar (2m), the popular Rosy Glow (1m-1.5m) and the beautiful variegated Silver Beauty (1m).
More compact varieties include lime-green Kobold and red Little Favourite, both growing to about 60cm. Kobold’s leaves turn gold in autumn, unlike the more fiery colours of most deciduous barberries.
Apart from their good colour range, lovely autumn colour and varying heights, barberries have other attributes.
Thanks to their spines, they make excellent hedges to deter intruders and a bush or two under a window is said to keep burglars out.
Except for the golden barberry, which is not quite as tough as the deciduous types, berberis are very hardy, which is why they have long been grown in Central Otago. Many have attractive little yellow spring flowers, sometimes scented, and they will grow in any type of soil, as long as it is well-drained. Deer do not eat them but rabbits will chomp young foliage.
Pruning can be done in spring when the shrubs have finished flowering, or in autumn, although that tends to mean chopping off next season’s flowers.
To keep the plants looking good, removing old stems at the base will promote new growth.
If you want more, Berberis can be grown from cuttings or by sowing the berries. Although seed-grown ones may not grow true, you may get something new and special, so it’s well worth a try.
