The ancestor of today’s violas is the sweet violet (Viola odorata) which is known for its compact plant growth and small, sweetly fragrant, deep violet flowers.
Garden violas are represented by two species. One species is Viola tricolor. This perennial is native to Europe and Asia and produces small flowers in purple, yellow, and white with interesting marks or whiskers.
The other is Viola cornuta, sometimes called tufted or horned pansy, or horned violet. Native to Spain and the Pyrenees, Viola cornuta grows throughout temperate regions of the world. Plants are compact with small flowers patterned with rays or lines in a deeper or contrasting color.
Closely related is the garden pansy (Viola wittrockiana), a short-lived perennial with larger flowers than V. tricolor or V. cornuta.