Dianthus barbatus (Sweet William) is a species of Dianthus native to the mountains of southern Europe from the Pyrenees east to the Carpathians and the Balkans, with a variety disjunct in northeastern China, Korea, and southeasternmost Russia.
It is a herbaceous biennial or short-lived perennial plant growing to 30-75 cm tall, with green to glaucous blue-green tapered leaves 4-10 cm long and 1-2 cm broad. The flowers are produced in a dense cluster of up to 30 at the top of the stems and have a spicy, clovelike scent; each flower is 2–3 cm diameter with five petals with serrated edges; in wild plants the petals are red with a white base.
There are two varieties:
It was introduced to northern Europe in the sixteenth century, and later to North America and elsewhere, and has become locally to widely naturalised in these areas.
Its traditional use is in landscaping and cut flowers. Gerard praises its beauty but omits any reference to medicinal uses. Its height makes it convenient for flower arrangements. In the Victorian language of flowers, Sweet William symbolizes gallantry. The plant is widely used in borders, rock gardens and informal country cottage style gardens. Sweet William is a good candidate for a naturalistic garden because its nectar attracts birds, bees and butterflies.
Its flowers are considered edible.
It thrives in loamy, slightly alkaline soil with sun to partial shade. Propagation is by seed, cuttings or division but seeds of cultivars will not breed true. If it is planted from seed after the last frost, it will flower in the second year. If it is planted in flats before the last frost and then transplanted it may flower in the first year. Some gardeners recommend deadheading to encourage further flowering. The plant is self-seeding.
In 1977 the question of possible medical uses was revisited by Cordell. Saponins with anti-inflammatory and analgesic effects were found in Sweet William. There has been little followup.
Many legends purport to explain how Sweet William acquired its name, but none is verified. It is variously said to be named after Saint William of York, William the Conqueror, or Prince William Augustus, Duke of Cumberland. Another etymological derivation is that william is a corruption of the French oillet, meaning "little eye". Sweet William is a favourite name for lovelorn young men in English folkloric ballads.