Dianthus barbatus

By: Sarah Keizer

Quick Facts:


Common Name: Sweet William

Family Name: Caryophyllaceae

Height: 1-2 Ft

Spread: 0.5-1 Ft

Light: Full Sun to Part Shade


Water: Dry to Medium moisture

Bloom Time: Late Spring to Summer

Bloom Color: Red, Pink, White, and Bicolor

Soil: Alkaline, Moist, and Well-Drained

Zone: 3-9

History: The Dianthus barbatus is not a new plant in the horticulture community. It has been around since ancient times and is native to Eurasia. The plant was named by Theophrastus, a Greek botanist. The name Dianthus comes from the Greek word dios which means ‘divine’ and anthous which means ‘flower’. This plant is commonly known as Sweet William and is in the same family as the carnation, Dianthus caryophyllus. Plants in this family are also known as “Pinks”. They received this name not because they come in the color pink but rather because the edges of their flowers appear to have been trimmed by ‘pinking shears’.


Growth: Dianthus barbatus is commonly known as a biennial, a plant with a two year life span, but because it can self-seed so easily it can be considered an annual. However, many people prefer to simply buy cold treated plant in the spring and grow them as annuals. As previously mentioned the Sweet William can be propagated by seed but also by division. The plant typically grows to be between one to two feet tall with smaller flowers in a dense, flat-topped terminal cluster that are between three to five inches wide. Sweet William has an upright, round shaped growth habit. Also by placing several plants together you can create a very nice mass of foliage and flowers. Dianthus barbatus does prefer to grow in a full sun to a part shade environment with well drained, slightly alkaline soil. A good tip is to add some lime into the planting soil and the Sweet William will be a much healthier plant.


Flowering: The bloom time for Dianthus barbatus is early spring to late summer before the first frost. Flowers on this plant are generally vibrant red, pink, or white, sometimes with a contrasting eye, and fringed, or ‘pinked’ five petals. It also comes in a bicolor combination of the previously mentioned colors. Sweet William’s flowers are said to be both showy and fragrant but many new cultivars are no longer fragrant. Plants do come in double-flowered forms and in some dwarf cultivars; they are between four to eight inches tall. You must deadhead the Dianthus barbatus after blooming if you wish to prolong the season.


Uses: Whether it is a bed, a border, or a container, Dianthus barbatus works well in almost any type of garden. It can also be grown as a cut-flower. Sweet William will also attract hummingbirds and butterflies into the garden.


Problems : Like most plants, Dianthus barbatus is not without problems. The plant is susceptible to crown rot and rust, especially when planted in poorly drained soil. In addition, you must keep an eye out for snails and slugs, also keep in mind that Sweet William does not tolerate the heat well.


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