Dianthus barbatus is believed to have been introduced to England by Carthusian monks as early as the 12th century. By the mid 1700's, it was growing in American colonial gardens.
Sweet William prefers full to partial sun and well-drained soil. Although a perennial, it is short lived, so most people treat it as a biennial. The first year plants will produce only foliage. In the second growing season, the clusters of flowers appear. Sweet William is an essential plant for the front of the cottage garden, growing 1-2' tall and producing clusters of fringed flowers in shades of red, pink, and white from late spring to early summer. Plants will reseed themselves at the end of the growing season.
Direct sow seeds into the garden in the late spring or early summer. Cover with ¼" of soil and keep moist but not wet. Germination will occur in 1-2 weeks at 70°F. Seeds may also be started indoors and transplanted into the garden, 12-18" apart, when they are 6-8 weeks old. If transplanted to the garden in early fall, expect flowers the following spring. USDA Zones 3-7.