Empetrum nigrum Bernstein

The Empetrum nigrum 'Bernstein' is a selection of Black crowberry with remarkable foliage throughout the year, ranging from golden yellow in summer to shades of orange and bronze in autumn and winter. It is an extremely hardy undershrub, ideal for ground cover in ericaceous beds. Its small flowers give way to edible black berries resembling blueberries. It is ideally placed near water features, in borders or cool rockeries, and in acidic and moist soil. To achieve fruiting, it is necessary to plant at least one male plant near this variety.

Empetrum nigrum 'Bernstein' belongs to the Heath family. The species is native to Northern Europe, Central Europe, Siberia, Japan, and northern North America. In the wild, this plant grows in turf bogs and marshes, in lowlands under the coldest climates, seeking refuge in high mountain ranges elsewhere. 

It is a slow-growing undershrub with a spreading habit forming a wide ground-covering cushion. As an adult, it will not exceed 20 cm (8in) in height and 50 cm (20in) in diameter. The vegetation of this plant consists of reddish and prostrate stems capable of rooting upon contact with the ground, becoming erect at their tips. The stems are densely covered with small, very narrow and leathery but non-prickly leaves: linear; they are rolled up on themselves and measure 4 to 6 mm (1in) in length and 1 to 2 mm (1in) in width. Their colour changes successively from green to golden yellow, then orange and bronze, from spring to winter. The discreet flowering usually takes place between May and June, depending on the climate. The tiny flowers, 1 to 2 mm (1in) in diameter with 6 tepals, are pink to purplish pink. In this dioecious plant, there are male and female individuals. Only the females will bear fruit, which ripen in September. These lovely berries are fleshy, sweet, and delicious: in Iceland, they are commonly used in delicious jams and to garnish succulent tarts.

Black crowberry 'Bernstein' is one of those shrubs requiring very little maintenance in favorable climate and soil conditions. It forms a variegated ground cover that remains attractive all year round, even in winter. Its small fruits are as tasty as they are rich in vitamins, valuable for helping young and old get through the winter. It is not difficult to find a place for it in the garden, and it is useful for covering the ground in difficult, peaty, or waterlogged areas. For example, several plants can be planted along a pathway, or a few individuals scattered in a rockery. It is an excellent companion for winter heathers, but also for other small undershrubs like gaultherias, or even burnets in not too cold climates.