Viola, genus of about 500 species of herbs or low shrubs, including the small, solid-coloured violets and the larger-flowered, often multicoloured violas and pansies.
Viola occur naturally worldwide but are found most abundantly in temperate climates, with the greatest variety occurring in the Andes Mountains of South America.
Wild Viola may be annuals or perennials. Because Viola freely hybridize, however, it is often difficult to identify their species.
The flower, variable in colour, but not red, usually grows singly on a stalk and has five petals, four arranged in unlike pairs, the fifth with a spur (see photograph).
The leaves may grow on the same stalk as the flower (stemmed violets) or on separate stalks (stemless violets).
Though the best-known Viola have heart-shaped leaves, the leaves of other species may have different shapes.