- Name also: Bog Whortleberry, Bog Blueberry
- Family: Heather Family – Ericaceae
- Growing form: Perennial dwarf shrub–small shrub.
- Height: 15–70 cm (6–30 in.). Stem erect (sometimes prodtrate), branched from base, woody, brownish, gray-haired.
- Flower: Corolla urceolate (pitcher-shaped), white–reddish, 4–6 mm (0.16–0.24 in.) long, fused, shallowly 4–5-lobed. Calyx shallowly 5-lobed. A single carpel. Stamens 8. Inflorescence a 1–3-flowered terminal raceme; flowers nodding.
- Leaves: Alternate, short-stalked, withering by winter. Blade obovate–elliptic, with entire margins, veins prominent, bluish green, matt.
- Fruit: Spherical–ovoid, often slightly angular, 8–12 mm (0.32–0.48 in.) broad, glaucous, matt, inside light-coloured, mild, juicy berry.
- Habitat: Bogs, swamps, forest heaths and fell moors.
- Flowering time: May–June.
The Heather family is very wide, and bog bilberry is its strongest representative in Finland. Of the northern species in the family, bog bilberry is the largest and it is very long-lived, surviving up to a hundred years. It is common in all of Finland: in the south of the country is grows straight as a small bush, but in the north it remains a low shrub. Like many other dwarf shrubs that grow in bogs it can thrive in Lapland in drier places as it can in the south too, in forest heaths and even fell tundra. Bog bilberry turns beautiful shades of purple, yellow, orange and red during autumn, especially in the north.
Bog bilberry is pollinated by insects, and its strongly fragranced flowers attract bees. The berry is juicy and has a mild flavour and varies between being round, egg-shaped, pear-shaped or with 4 rounded corners. For some reason bog bilberry’s fruit has never been highly prized in Finland, and the economic worth of the species is almost non-existent. Finnish bog bilberry berries are certainly more watery than other related fruit that grows in the northern hemisphere, but claims that it is poisonous are completely groundless. This is also true of the belief that eating the berries gives you intestinal worms and ugly children! According to one groundless belief, eating a large amount of the berries causes a hangover type of headache, and some of the plant’s Finnish folk names reflect this. Bog bilberry suits well in mixed berry juices and jams with blueberry, crowberry or blackcurrant. Crossing bog bilberry with North American blueberries has resulted in the first variety of cultivated blueberry (Aron) that thrives in the Finnish environment.