Vaccinium myrtillus aka Bilberry

Vaccinium myrtillus, or bilberry, belongs to the heath family, Ericaceae. This small shrub loses its leaves in winter. Its native range spans Greenland and much of temperate Eurasia. It also grows wild in western Canada and parts of the western United States. It is native to Britain and Ireland. Wild plants grow on acid heaths, moors and in woods.

Bilberry grows low and spreads through suckers and rhizomes. Its many branches can form dense patches. Plants often stay below 1 foot [0.3 m] tall. The RHS gives a garden height range of 0.3–1.6 feet [0.1–0.5 m]. Garden spread reaches 1.6–3.3 feet [0.5–1 m]. Plants may take 10–20 years to reach full size. Young stems are green, slender and sharply angled. Smooth bark turns reddish brown with age. The glossy leaves are oval, with fine teeth along their edges. They grow alternately and have paler undersides. Leaves often turn red in autumn.

Small pink flowers hang singly where leaves join the stems. Their rounded, bell-like or urn-shaped blooms appear from late spring into early summer. Blue-black berries follow, with red flesh and small seeds. The fruit tastes sweet with a slight sharpness. People eat it fresh, cook it or make jam. Dried berries can serve much like currants. The leaves also have a history of use in tea. Leaves and fruit supply dyes; fruit can also make ink.

Grow bilberry in acid soil with good drainage. It suits sandy or loamy ground, including naturally peaty soil. Keep the soil moist without leaving it waterlogged. It grows in full sun or partial shade. Woodland edges and dappled shade also suit it. The RHS rates its hardiness H6; PFAF lists USDA zones 3–7. Its low, spreading growth suits ground cover, banks and slopes. It also fits wildlife gardens and plantings grown for edible fruit. Grow new plants from seed or semi-ripe cuttings.

Pests seldom cause trouble, but several diseases can affect bilberry. These include powdery mildew, root rot and, less often, honey fungus. Iron or manganese shortages can cause chlorosis. PFAF records medicinal uses but also warns about tannins. Large amounts or long use may upset digestion. It advises avoiding medicinal use during pregnancy or while taking anticoagulants. These cautions matter when using leaves or concentrated preparations, despite the fruit's food use.