Dainty violet (Viola spp. and cultivars) flowers amid heart-shaped leaves have been a favorite garden subject for centuries. There are about 400 species of violets native to both Northern and Southern Hemisphere temperate forests, and many garden cultivars. Flower colors include white, pink, red, blue, lavender and purple, and a cultivar can exhibit variable color depending on where and how it is grown. Violets can be fragrant or scentless. Purple violets include some of the most fragrant and showy cultivars.
These intensely fragrant violets are heirloom plants, grown in Italy from the 16th century. They were a favorite of the Bourbon kings and of Napoleon and his second wife, Marie Louise. Parma violets (V. alba cultivars) are double-flowered and grow in U.S. Department of Agriculture zones 7 through 9. "Parme de Toulouse" flowers are bluish-purple to rosy purple; "Marie Louise" ranges from soft to deep purple, and is the most widely grown of the Parma violets. These cultivars appreciate partial shade and a well-draining soil.
Another fragrant purple flower belongs to sweet violet (V. odorata), but it is not as sweet-smelling as Parma violets. Also called wood violet, English violet, florist's violet and garden violet, this species is native to Europe and Asia but is now grown worldwide. Sweet violet cultivars occur in many colors, including white, blue, lilac, rose, red, royal purple and violet. The main bloom periods are in spring and fall, with some summer and winter rebloom in mild winter areas. Sweet violet grows in USDA zones 6 through 8.
Suitable for wet areas, marsh violet (V. obliqua, formerly V. cucullata), also called purple violet, spreads underground by means of fleshy rhizomes. Plants are 2 inches tall and 4 to 6 inches wide. Flowers range from blue-violet to pale blue to white. It blooms in late spring and does not have a fragrance. Plants grow in USDA zones 4 through 9. Kidney-shaped leaves have teeth along the margins. Native to eastern North America, marsh violet tolerates both partial and full shade.
Purple Labrador Violet
This low-growing native of eastern North America has small light-purple flowers in spring and fall, and also in cool summers. Purple Labrador violet (V. riviniana, formerly V. labradorica) prefers cool, moist rich soil and partial to full shade, such as under deciduous trees. Heart-shaped leaves are tinged with purple as well. This violet is good for borders, edgings, massed plantings and containers, combining nicely with other plants with colored leaves. Flowers are not fragrant. Plants grow in USDA zones 3 through 9.
- The American Violet Society: Classification of the Cultivated Forms of the Genus Viola
- The American Violet Society: Parma Violets
- American Journal of Botany: On the Origin of the Sweet-Smelling Parma Violet Cultivars ...
- The Best of Fine Gardening: Perennials; Fine Gardening
- American Horticultural Society Encyclopedia of Plants and Flowers; Christopher Brickell
- Plants For a Future: Viola Obliqua - Aiton.
- Perennials.com: Viola Labradorica
- Mother Earth Living: Sweet Violet Plants
- Christian Science Monitor: The Very Fragrant Parma Violet
- White Lotus Aromatics: Violets of Grasse Newsletter
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