Plant Portrait - Viola odorata Sweet Violet
This article originally appeared in the Jan 1998 edition of the Friends of PFAF newsletter.
The sweet violet is an evergreen perennial woodland plant growing about 10cm tall and forming a carpet of growth that makes a good weed-excluding ground cover. The edible leaves can be harvested all year round, and the edible flowers are produced in late winter and early spring.
This is a very easily grown plant, although by nature it grows mainly in the dappled shade of a woodland, it is very tolerant and will even succeed in very hot, sunny positions so long as the soil does not dry out. It succeeds in most soils but prefers a cool moist well-drained humus-rich soil in partial or dappled shade and protection from scorching winds. When grown in the open it prefers a moderately heavy rich soil. We have even see it thriving in old stone walls so long as there are small pockets of soil for it to get its roots into. The plants are very cold-hardy and will tolerate temperatures down to about -20°c.
The leaves are quite small, perhaps 3 - 5cm in diameter, but are produced in abundance and are easy to harvest. They have a very mild, almost bland flavour and can be used in quantities in salads. The texture is slightly tough, however, so we usually mix them in well with other leaves. The leaves can also be cooked, and are a nice addition to soups or stews where they will help to thicken them in much the same way as okra can be used.
My favourite part is the flowers. These are usually produced in abundance in late winter and early spring. They have a strong scent and taste of parma violet and make a superb and decorative addition to salads
Sweet violets have various other uses in the garden, including various medicinal uses. For example, it has a strong folk reputation in the treatment of cancer and whooping cough. It also contains salicylic acid, which is used to make aspirin, and is therefore effective in the treatment of headaches, migraine and insomnia. An essential oil from the flowers and leaves is used in perfumery and the flowers themselves are used to flavour breath fresheners.
Propagation is easiest by division of an established plant. Simply break off a small section that has roots, pot it up for a few weeks until established and then plant out. Spring is perhaps the best time to do this, but we find that it works well just about any time.
Seed is best sown in the autumn in a cold frame. The seed requires a period of cold stratification and the germination of stored seed can be erratic. Prick out the seedlings into individual pots when they are large enough to handle and plant them out in the summer.
The database has more details on these plants: Viola odorata.