Approximate ranges of the cranberries in sect. Oxycoccos: Red: Common Cranberry. Orange: Small Cranberry. Green: American Cranberry. Cranberries are a group of evergreen dwarf shrubs or trailing vines in the genus Vaccinium subgenus Oxycoccos, or in some treatments, in the distinct genus Oxycoccos. They are found in acidic bogs throughout the cooler parts of the Northern Hemisphere.

Cranberries are low, creeping shrubs or vines up to 2 m long and 5 to 20 cm in height; they have slender, wiry stems that are not thickly woody and have small evergreen leaves. The flowers are dark pink, with very distinct reflexed petals, leaving the style and stamens fully exposed and pointing forward. They are pollinated by domestic honey bees. The fruit is an epigynous berry that is larger than the leaves of the plant; it is initially white, but turns a deep red when fully ripe. It is edible, with an acidic taste that can overwhelm its sweetness.

Cranberries are a major commercial crop in certain American states and Canadian provinces (see "Cultivation and Uses" below). Most cranberries are processed into products such as juice, sauce, and sweetened dried cranberries (e.g. Craisins), with the remainder sold fresh to consumers. Cranberry sauce is regarded an indispensable part of traditional American and Canadian Thanksgiving menus and European winter festivals.

Since the early 21st century within the global functional food industry, there has been a rapidly growing recognition of cranberries for their consumer product popularity, nutrient content and antioxidant qualities, giving them commercial status as a "superfruit".

Species and description

There are three to four species of cranberry, classified in two sections:

Subgenus Oxycoccos, sect. Oxycoccos

• Vaccinium oxycoccos or Oxycoccos palustris (Common Cranberry or Northern Cranberry) is widespread throughout the cool temperate Northern Hemisphere, including northern Europe, northern Asia and northern North America. It has small 5-10 mm leaves. The flowers are dark pink, with a purple central spike, produced on finely hairy stems. The fruit is a small pale pink berry, with a refreshing sharp acidic flavour.
• Vaccinium microcarpum or Oxycoccos microcarpus (Small Cranberry) occurs in northern Europe and northern Asia, and differs from V. oxycoccus in the leaves being more triangular, and the flower stems hairless. Some botanists include it within V. oxycoccos.
• Vaccinium macrocarpon or Oxycoccos macrocarpus (Large cranberry, American Cranberry, Bearberry) native to northeastern North America (eastern Canada, and eastern United States, south to North Carolina at high altitudes). It differs from V. oxycoccus in the leaves being larger, 10-20 mm long, and in its slightly apple-like taste.