Apart from the florist's Violas and the Sweet Violet there are several natural species grown for rock gardening and borders, among them being the following: biflora, 3 in., yellow, May to June; calcarata, 3 in., pale mauve, May to June, with a few forms; cornuta, 6 in., deep blue, with a white variety, April to August; cucculata, 6 in., pale to deep violet, with a white variety; gracilis, 3-6 in., deep violet blue, April to August; Munbyana, 6 in., violet, with a yellow form (lutea), spring to autumn; pedata, 3 in., bright blue, but mauve and violet in the variety bicolor and white in alba, April to July. They like a deep loamy soil with plenty of sand and leaf mould, and are increased by division and seeds.