Scientific: Dianthus barbatus
Common: sweet Willam
Family: Caryophyllaceae
Origin: Europe
Pronounciation: Di-AN-thus bar-BAY-tus
Hardiness zones
Sunset All zones
USDA All zones
Landscape Use: Edging plant for landscape borders, colorful when planted in mass in flower beds, patio containers or hanging baskets.
Form & Character: Low, mounding, bright, warm, and cheery.
Growth Habit: Evergreen, herbaceous biennial grown as cool season annual in Phoenix, grows to 12 to 16 inches in height with equal or less spread.
Foliage/Texture: Medium green to slightly glaucous, linear to lanceolate leaves to 2 to 3 inches, sessile; fine texture.
Flowers & Fruits: Terminal clusters of rounded flowers w/ splayed margins, many colors and bicolors, fruit inconspicuous.
Seasonal Color: Winter and Spring, purple, red, pinks, and white, bi-colors.
Temperature: Prefers temperatures between 25oF and 90oF which means in Phoenix that one sets plants out in late September and can rely on them for a good show of color until late April or early May in Phoenix.
Light: Full sun
Soil: Well drained w/ ample organic matter is best so as to maintain high fertility and good water holding capacity, in other words....a good garden soil!
Watering: Apply regular water at all times even in winter
Pruning: None
Propagation: Seed
Disease and Pests: None
Additional comments: Sweet William is one of the most consistent cool season bedding plants for the Phoenix area. Set out transplants in early October at about 6 to 8 inches on center. Dianthus barbatus used in combination with Lobelia erinus make a wonderful color combination for residential and commercial entryways during the Phoenix cool season of late October to mid April. Sweet William sometimes reseeds and might survive until July in Phoenix if planted in an eastern exposure location with copious mid-day and afternoon shade. There are a plethora of cultivars of many single and multi-colors, new ones are introduced each year.
Some noteworthy cultivar examples:
A Dianthus menagerie: Dianthus barbatus, Dianthus chinensis (Chinese pinks) and Dianthus deltoides (maiden pink) have increasingly been hybrdized with other Dianthus species to yield a myriad of wonderful cultivated selections for landscape color of various flower colors and plant growth habit.
