A sub-species exists:
Mountain Crowberry (Empetrum nigrum ssp. hermaphroditum) which is shorter and grows in high mountainous areas, especially in Scotland. On the sub-species, male and female parts of the flower are on the same plant, hence the name hermaphroditum, whereas on Crowberry itself they are on separate plants.
Slight resemblance to : The leaves are similar to those of Biting Stonecrop, English Stonecrop and White Stonecrop in that they are short, stubby and fleshy.
Not to be confused with: Cowberry [a plant with similar name, which also belongs to the same Family].
Uniquely identifiable characteristics: Although the berry can look similar to that of Bearberry or Arctic Bearberry when pink or purple, it is slightly larger, and ends up black rather than the red of Bearberry.
Distinguishing Feature : It is the evergreen leaves which are short, stubby, glossy green and fleshy that give it away most easily.
The flowers of this evergreen undershrub are very small and reside in the axils of the (short) bulbous leaves. They are pale pinkish and have five petals. It is dioecious, with male and female flowers on separate plants (except for the sub-species ssp. hermaphroditum which is hermaphroditic). The fruit is a large black berry which is green at first turning pink then purple before ending up black.
Crowberry used to belong all on its own in the Crowberry Family (Empetraceae), but that has now been abandoned and Crowberry transferred to the Heather Family.
The juice from the berries has a high concentration of purple and black anthocyanin dyes which can be used for colouring foodstuffs etc. The berry is edible raw, but cooking enhances the flavour, and it can be used in jams and tarts. The berries will remain on the plant until the spring unless picked, and are still edible. Vitamin content is low as are volatile odorous liquids, the berries are nearly aromaless.