Part used: aerial parts
There are over 90 Viola species in Europe. The Flora of Turkey gives 20 Viola species, including Viola odorata and Viola tricolor.
Viola odorata L. is a low-growing perennial with a stout rootstock found in hedgerows, rough land and margins of woodlands. It is native to Europe south of the Alps and west into France, but has naturalized in more northern areas because of widespread cultivation.
The stalked leaves arise in a rosette from the sturdy rootstock and are heart-shaped and hairy with an oval stipule. The fragrant, five-petalled dark violet or white flowers occur in spring and it may flower again in early autumn. The leafless flower stalks curve sharply so that the flower hangs down. The lowest petal has a prominent nectar-filled spur and the five sepals have basal appendages. The small seeds form in a three-valved capsule and it also spreads by long creeping stolons.
Other species used
Parma violets are cultivated for cut flowers and for their fragrance. The leaves are shiny green and the flowers are double. A study of six specimens cultivated in France and 31 wild Viola species found that Parma violets are cultivars of Viola alba. Parma violets are tender and flower from autumn to spring depending on the variety. They are considered to have been introduced to Europe, certainly by the early 19th century as they were grown alongside many other violets in the gardens of the Empress Josephine at Malmaison. The violet became a symbol of the House of Bonaparte. In the 19th century, cultivation of numerous varieties in market gardens and orchards, for cut flowers and button holes was an enormous trade in northern and southern France and England, especially in Middlesex.
Viola yedoensis is a perennial and is used in China in the treatment of acute skin infections.
Other common species of violet are scented or faintly scented and are not used. White violet Viola alba is white with non-rooting runners. Hairy violet Viola hirta is similar to Viola odorata but hairy with no runners and usually found on chalk or limestone. Viola x scabra is the cross between Viola hirta and Viola odorata. Early dog-violet Viola reichenbachiana and common dog-violet Viola riviniana have veined throats, more pointed leaves, and flowers and leaves arise from the same stems. Marsh violet Viola palustris has veined pale violet flowers and rounded leaves. Field pansy Viola arvensis is similar to Viola tricolor with creamy yellow flowers and longer sepals and the two species form crosses which are difficult to distinguish. Viola species are illustrated in Gibbons & Brough (1996).
Sweet Violet: Quality
Given the similarity between species, it is hard to believe that only the leaves of Viola odorata are collected. The French Pharmacopoeia includes Viola lutea and Viola calcarata. Leaves of the many aromatic cultivars could be collected as they are cultivars rather than hybrids.
A Cooling Herb
The current uses of viola appear to be somewhat metamorphosed within its broad ancient themes, referring to a diverse and sporadic tradition in some degree, with some expansions and one or two additions. Chevallier and Hoffman record its main use now as a cough remedy, for coughs, colds and catarrh. Hoffman expands on its alterative and antiinflammatory properties, useful in skin conditions, urinary tract infections and rheumatism. Both authors cite recent application for cancer. The British Herbal Pharmacopoeia specifies it expectorant and antineoplastic.
Violet nature, according to tradition, is cooling. It belongs to a smaller group of plants, cold and moist in nature, which treat either symptoms of heat or dryness. This cooling property is employed, according to Dioscorides (IV 121), to ease heartburn, eye inflammations and prolapse of the anus, as external application of the leaves as a plaster. The purple flower helps in sore throats and in epilepsy in children, the infusion taken internally. Pliny expands on this. He records purple, white and yellow varieties. The purple, as Dioscorides but with no distinction as to leaves or flowers, is applied for stomach inflammation, to the forehead when the head burns, for watering eyes, anal and uterine prolapse, and he adds its use for abscesses. Moreover, violets are placed on the head to disperse the after effects of drinking and its headaches; then follows use in water for quinsies and for epilepsy in children, again as Dioscorides. Its seed neutralizes scorpion stings. The white and yellow violets, to be used dried and over 1 year old to increase their potency, are diuretic, reduce menstrual discharge; the white disperse abscesses, while the yellow, half a cyathus (22 mL) in 3 cyathi of water (135 mL), promotes menstruation. Its roots, presumably the yellow variety, although he does not specify, with vinegar as liniment, soothe the spleen and gout, while for eye inflammations myrrh Commiphora molmol and saffron Crocus sativus are added. With wax ointment they, again presumably the yellow, heal cracks in the anus and other moist parts of the body; in vinegar they heal abscesses. Galen ascribes the virtues of violets to their cool, watery nature. Topically with polenta they are good for hot inflammations, a burning mouth of the stomach and the eyes. So with some few additions from Pliny, our three ancient sources mainly converge. So far, there is no mention specifically of use for cough, though quinsy is at least heading in that direction.
• Syrup of flowers for coughs, colds and catarrh.
• Syrup as laxative for children.
• Leaves as antiinflammatory in fevers and rheumatism.
• A cooling demulcent for urinary conditions.
• A cooling liver herb for bile/bilious conditions.
• For indications of heat – heartburn, anger.
Dosage: the British Herbal Pharmacopoeia recommends 2-4 g three times a day of dried herb but the history of use of violets indicates fresh leaf preparations, mainly the syrup for children in Quincys dose of %-l fl oz (7-30 mL) and as a vehicle for stronger lung remedies for adults.
Since herbalists today are just as likely to prescribe another Viola species, namely Viola tricolor, we have included a discussion of this herb for completeness.
Viola Odorata Constituents
Mucilage 18% (flowers, wild, France).
Mucilage, mainly galactose, glucose and galacturonic acid (leaves, wild, Russia).
var. Parma, total 0.02%, characteristic aliphatic aldehydes: nona-2,6-dienal; aliphatic alcohols (leaf, cultivated, France).
Flowers, total 0.003% diethylphthalate 26%, alpha-curcumene 18%, zingiberene 17%, dihydro-beta-ionone 10%; trans-alpha-ionone gives the characteristic fragrance.
Anthocyanins 4%, total flavonoids 1.1 %: flavonol glycosides (flowers, wild, France).
Leaf, flower, methyl salicylate.
Leaf, macrocyclic peptides with 28-37 amino acids, which are very stable because of a unique knot formed of three disulfide bonds in a cysteine knot. They are common in Violaceae such as Viola odorata and may have a cytotoxic action through disruption of membranes.