Berberis x stenophylla - Barberry

Berberis x stenophylla, or narrow-leaved barberry, is a recognised hybrid known for its vigour and ease of cultivation even in difficult soil. This hybrid develops a dense bushy habit with gracefully arching branches that bear small, narrow, evergreen leaves. The leaves are dark green and shiny on the upper side and glaucous on the lower side. From May to June, it produces charming short clusters of golden-yellow, fragrant flowers followed by small, blue-black, pruinose berries that adorn the bush until late autumn. These berries provide a substantial food source for birds, who already take advantage of its compact branching to build their nests. Hardy and resistant to salt spray and pollution, it is an ideal shrub for creating ecological defensive hedges that are beautiful throughout the year. Plant it in full sun or partial shade in well-drained soils, including limestone, clay, dry, or poor soils.

The narrow-leaved barberry is an ancient English hybrid dating back to 1860, resulting from the cross-breeding of Berberis darwinii and B. empetrifolia. Its two parents are shrubs from the Berberidaceae family, native to South America. This hybrid inherits their hardiness, resistance, and tolerance to poor soils.

Berberis x stenophylla has a bushy, dense, branching habit that spreads more in width, carried by round, slender, and arching branches that turn reddish-brown at maturity. The stems of this shrub bear thorns that are 3 mm to 7 mm (0.2 in to 0.3 in) long. Its growth rate is moderate, reaching an average height of 3 m (9.8 ft) and an average width of 4 m (13.1 ft). From May to June, depending on the climate, numerous short, pendant clusters of 4 cm to 10 cm (1.6 in to 3.9 in) develop on 1-year-old stems. The clusters have reddish peduncles and bear 2 to 6 small flowers. The bell-shaped flowers, 1 cm (0.4 in) long, are golden-yellow with a red wash. They are highly nectar-rich and are followed by small, fleshy, ovoid fruits that are pruinose and dark blue-black, measuring 7 mm (0.3 in) in length. The persistent foliage is another asset of this barberry. It consists of small, narrow leaves, 1.5 cm to 2.5 cm (0.6 in to 1 in) long, slightly incurved, leathery, dark green, and glaucous on the underside. They bear a terminal spine.

Berberis x stenophylla should be more commonly planted in our gardens. It can perfectly replace Pyracantha in a medium-sized defensive hedge, which should be pruned sparingly as its naturally dense and neat habit does not require excessive pruning. While its berries may be less spectacular than those of Pyracantha, it offers the advantage of maintaining modest dimensions and blooming twice, all while providing more elegant foliage. However, it is a shame to confine it to the role of an anonymous defensive hedge shrub; although it accomplishes its mission perfectly, its personality is somewhat hidden. It deserves to be highlighted alongside variegated foliage or in front of a screen of taller shrubs with colourful flowers: blue (Ceanothus 'Puget Blue'), pink, purple, or white (Abelia), red (Japanese quince), or even yellow to orange (Kerria japonica, Genista 'Lena Orange', Lonicera 'Dropmore Scarlett'). Some gardeners, with great originality, train it as a small single-trunk tree. This shrub can also be planted in large rockeries to cover slopes or be planted as a standalone specimen where its aesthetic appeal can be enjoyed all year round.

Did you know?

While the immature fruits are toxic due to a molecule called berberine, which degrades during fruit ripening, their very acidic taste is not appreciated, and they contain many seeds. In South America, the bark rich in tannins and the roots are used to treat dysentery. A yellow pigment is also extracted from the roots and used to dye textiles.