Viola is a genus with an unusually wide distribution, through most of both northern and southern hemispheres. They include some widespread and easily grown British natives, and South American rosette-forming species that are almost impossible to cultivate. Sadly, we don't have that last group, but our list includes some that are rarely offered for sale in Britain. All have the characteristics viola or pansy flowers.

Viola cornuta provides welcome colour for a long period on our rock garden, gently seeding itself about, but easily removed where it trespasses on other plants' space. We have two colour forms, which seem to come true from seed, although we haven't carried out rigorous scientific experiments. Under this name are plants with flowers of a soft mauve-blue colour.