Family: Violaceae
Common Name: Pansy, Violet, Viola

Of the 500 species of hardy annuals or perenni­als in this genus, most are from temperate parts of the northern hemisphere, with a few from Australia and New Zealand. Most viola species are best mass planted as annual displays, garden edging, in rockeries or containers. In semi-shade or damp spots, violets make fra­grant groundcovers.

Species

V. betonicifolia, wild violet, zone 9, is an Australian species with a wide distribution. A tufted plant, it has blue-purple flowers and oblong leaves.

V. cornuta, viola or horned violet, zone 7, is a tufted plant, to 30 cm (12 in), with oval, toothed leaves and large stipules. The common garden viola is a hybrid of this species and originally had small flowers of one or two colours, but with recent breeding it is becoming more like a true pansy. Many colour forms are available in single or mixed strains. New cultivars of garden violas are appearing all the time, so consult a good retail seed catalogue to find out what is suitable for an area.

V. filicaulis, zone 9, from New Zealand, has glossy, heart-shaped leaves and yellow flowers on very slender stems.

V. hederacea, Australian violet, zone 9, makes a useful groundcover. It has round leaves and delicate, blueish purple and white flowers on short stems.

V. lutea, zone 5, is a leafy plant, to 20 cm (8 in), with creeping stems. The flowers may be yellow, purple, or purple and yellow.

V. odorata, English or sweet violet, zone 8, from Europe, is the best known species, grown both in the home garden and commercially for perfume manufacture and floristry. A tuft-forming, spreading perennial, it has oval, toothed leaves and fragrant flowers, to 2 cm (¾ in) or more across, in deep violet, blue or white, with a short spur. The various forms and cultivars available include the white 'Alba' and double-flowered 'Alba Plena'. There are also double cultivars in other colours. V. septen­trionalis, zone 4, a perennial from North America, grows to 15 cm (6 in) high, with toothed, oval to heart-shaped, hairy leaves and large, blueish purple, sometimes white, flowers.

V. tricolor, wild pansy or heartsease, zone 4, from Europe, is an annual, to 30 cm (12 in). The leaves are oval to lance-shaped and the flowers are in combinations of purple, white, blue and yellow. Several cultivars are available, including the almost black Bowles' Black'.

V. x wittrockiana cultivars, pansies, zone 7, are from crossing the species V. altaica, V. cor­nuta, V. lutea and V. tricolor. The pansy is a favourite annual for bedding and borders and for container growing. The flowers have a velvety texture and the colour range is vast. Many are two or three toned and have attractive mark­ings. Low growing, to a maximum of 25 cm (10 in), the leaves are heart-shaped, with slightly lobed margins. With regular dead-head­ing, they have a long flowering period. There is a huge cultivar range for summer and winter-spring flowering. A good seed catalogue will list a comprehensive selection.

Cultivation

Plant violas in full sun or partial shade, depending on species and climate. Species grown as annuals generally need full sun. They do best in humus-rich soil that drains well. Water regularly and thoroughly in hot or windy weather, but keep much drier during winter. Regular removal of spent flowers will prolong the flowering display. Many are propa­gated from seed, especially those grown as annuals. Some perennial species can be propa­gated from tip cuttings taken in summer. Clumps of perennial forms can also be divided.

Climate

There are species suited to various climatic zones.