Empetrum nigrum aka Crowberry

Empetrum nigrum, or black crowberry, belongs to the heath family, Ericaceae. This evergreen shrub grows across the northern hemisphere. Its native range spans subarctic regions and high mountain zones. It occurs in Europe, Asia, and North America. It is native to Britain and Ireland. Wild plants grow on moors and mountain tops. They also occupy the drier parts of blanket bogs.

Crowberry forms a low mat with stems that trail outward. Plants often stand about 0.5 feet [0.15 metres] tall. The RHS gives a garden height range of 0.3–1.6 feet [0.1–0.5 metres]. Spread reaches 1.6–3.3 feet [0.5–1 metre]. Small, plump leaves resemble needles but have blunt tips. They crowd the stems, giving shoots a brush-like look. Slender young stems range from green to reddish brown. They carry sparse soft hairs, while bark is reddish brown.

Small pink or purple flowers appear in spring and summer. The RHS places flowering in late spring and early summer. Chicago Botanic Garden lists bloom from May through August. Most plants bear male and female flowers on separate plants. Dark berries ripen in autumn and may last through winter. The fruit is black, though some berries look dark purple. Most berries are small; reported sizes reach about half an inch.

Grow crowberry in an open spot with sun or partial shade. It suits cool places where rainfall is high. Give it acid soil that stays moist but drains well. The RHS lists clay, loam, and sand as suitable soils. Avoid soil that holds standing water around the roots. Its hardiness ratings are USDA zones 3–8 and UK H7. It works as ground cover, including in exposed sites. Its low form also suits the edges of woodland gardens. Plants need no routine pruning and rarely suffer pests or disease. Propagate them by layering or summer semi-ripe cuttings.

The berries can be eaten fresh or cooked. Their taste ranges from mildly sour to rather bland. People use them in drinks, pies, and preserves. Inuit communities dry or freeze the fruit for winter. The berries also yield a purple dye. Twigs can be used to make tea. Plants For A Future reports no known hazards. It records traditional uses for fever, kidney trouble, and diarrhoea. Those records describe past use, not proof of medical benefit.