Dianthus barbatus (Sweet William) is a biennial or short-lived perennial that is often grown as an annual. It thrives in loamy, slightly alkaline soil in sun or partial shade in hot summer climates. The flowers grow in rounded, dense clusters. Colors range from white through intense red and purple, often bicolor. There are many cultivars available, including double-flowered and dwarf forms. The epithet ‘ barbatus’ refers to the barbed or beard-like growth arising from the petals.