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Courtesy of National Garden Bureau

For centuries, Dianthus has been one of the most sought after plants for various landscapes. Its popularity comes in part from its ease of growing, but even more so from its palette of colors. Blooms present not only bright, solid colors—white, red, rose, dark red, lavender, pink, and the elusive yellow (D. knappii)—but also bicolors: picotees, with solid colors edged in white or a paler hue; “eyed” blooms with dark marks at their centers; streaks and multi-colored blooms on one plant.

Add foliage that ranges from bright green to gray-green, spicy fragrance in many species, and plant size that runs the gamut from petite 6-inch plants for edging a perennial garden, highlighting or a rock garden, to 3-foot specimens suitable for borders and cutting gardens, and you can understand why green industry professionals get excited about this variable genus. Read on about some of the more popular species and hybrids and how to raise them successfully in your landscapes.

THE NAMING OF PLANTS
The genus Dianthus contains about 300 species, but only a rather small number warrant attention. Dianthus, is from the Greek words for “flower of the gods” (meaning Zeus; Jove, or Jupiter, to the Romans). Dianthus is in the family Caryophyllaceae, a name derived from the Greek for clove tree, a reference to the often clove-scented blooms.

There are only four Dianthus species that are readily available for gardeners. Each is described below with a selection of varieties for reference.

* Dianthus barbatus (Dye-ANN-thus bar-BAY-tus) is the familiar sweet william of countless old-fashioned cottage gardens, a short-lived perennial or biennial. Newer varieties are annual flowering. The blooms of the species and many hybrids have a central spot, or eye. Native to southern Europe, sweet william is winter-hardy to Zone 4 and grows from 5 inches to 2 feet tall. Its single, sometimes double, flowers appear in dense clusters from late spring through summer. Flowers may or may not be fragrant. Some very old varieties still grace gardens, like the open-pollinated ‘Wee Willie’ which grows a petite 5 inches tall and produces early, single flowers. Other, more modern varieties range from the open-pollinated ‘Pinocchio Mix,’ a dwarf biennial, and the ‘Giant Imperial’ series, a tall biennial, to tall annual F1 hybrids such as the ‘Hollandia’ series and ‘Cinderella Mix,’ a hybrid for the cutting garden. ‘Amazon Neon Duo’ flowers are a 50:50 mixture of cherry and purple. The 18- to 24-inch Amazon does double duty as a perennial (Zone 5) and as a cutflower. ‘Noverna’ and ‘Heritage’ series are new, medium-tall annuals.

* D. chinensis (Chin-NEN-sis) a.k.a. China pinks, can be an annual or biennial or short-lived perennial (hardy to Zone 7), though all the best varieties or series on the market today will flower as an annual - first year from seed. Originally from China, plants tend to be dwarf, 6 to 10 inches tall, but may reach 18 inches. They produce single (occasionally double), small, scentless flowers intermittently all summer. These carefree plants need little maintenance; deadheading is not required for them to continue to bloom. The common name, pink, refers not to the color of the blooms but to their serrated edges; to “pink” (with slightly different spelling of pynken) meant to cut or notch in old-English—think of pinking shears. Actually, the word for the color pink comes from the name of the flower, not the other way around. Some of the best among open-pollinated varieties are ‘Persian Carpet,’ ‘Pastel Bedder’ and ‘China Doll’ (a 1970 All-America Selections Winner). Hybrids ‘Snowfire’ (1978 AAS winner), ‘Magic Charms’ (1974 AAS winner) and ‘Corona Cherry Magic’ (2003 AAS winner) offer F1 vigor and unusual colors. The blooms of the latter combine solid cherry, lavender with cherry center and tie-dyed lavender/cherry on the same plant for a striking show. ‘Raspberry Parfait’ as featured on the front cover, reaches a full sun garden height of 6 to 8 inches and spreads 8 to10 inches in USDA Hardiness Zone 5, AHS Heat Zone 9-1.

* D. chinensis x barbatus. One of the most common interspecific crosses, this group combines the best of both species. Hybrids from these crosses flower more freely and tolerate more heat and frost than either of the individual species. Blooms tend to be larger as well and appear in terminal clusters. Plants may be annual or biennial, but if you start them early enough indoors they will flower the first year from seed. ‘Ideal Violet’ with bright green leaves, won an AAS award in 1992. The ‘Ideal’ series contains 18 colors. Plants are heat and frost tolerant reaching 8 to 10 inches. ‘Ideal Cherry Picotee’ flowers are a bicolor design with a pink flower edge.

* Other interspecific hybrids. Because Dianthus species cross-pollinate so readily, they produce hybrids easily. Many hybrids have barbatus as one parent with the other parent unknown, except to the breeder. Interspecific hybrids may be annual, biennial, or perennial. They offer color all season on plants that flower freely and tolerate heat and tough situations. ‘Bouquet Purple’ is a prime example; excellent as part of a cutting garden or in a border, it produces tall, sturdy stems and lacy, lightly fragrant flowers. ‘Melody Pink’ (2000 AAS winner) is another; an annual bred to be a cut flower, it grows to about 2 feet but spreads to only 10 to 12 inches and produces clusters of single flowers. F1 ‘Dynasty Purple’ is a lightly scented double flowered Dianthus with a garden height of 18 to 19 inches.

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