Culture
Easily grown in average, evenly moist, well-drained soils in full sun. Plants require lots of sun for good flowers, but prefer cool summer temperatures. Plants generally perform best in organically rich, gritty loams in neutral to slightly alkaline soils. Good drainage is essential, but incorporating leaf mold and other organic material into the soil helps retain some moisture which is often needed in hot summer climates. Deadhead spent flowers to encourage additional bloom. Consider shearing plants back after main flush of bloom in order to tidy the planting and to promote additional bloom in late summer or early fall.
Noteworthy Characteristics
Perennial dianthus, commonly called carnations or pinks, are loosely-tufted, herbaceous perennials that features fragrant, often double flowers on stiff stems clad with narrow, linear, gray-green leaves. Most hybrid carnations are crosses between three species: D. caryophyllus, D. gratianopolitanus, and D. plumarius. There are thousands of carnation cultivars and hybrids which have been developed over time for use in both outdoor gardens or under glass for the cut flower industry. Extensive breeding has produced cultivars in almost every shade of pink, purple, red, orange, yellow, and white, and ranging in size from 6” tall up to long-stemmed plants rising to as much as 4’ tall.
Large-flowered carnations today are divided for organizational purposes into two different groupings: (1) border carnations (fragrant double flowers on stems rising to 16” tall) for use in outdoor gardens and (2) florist’s carnations (fragrant double flowers on stems rising to 3-4’ tall) primarily grown in greenhouses for supplying the florist trade.
Genus name comes from the Greek words dios meaning divine and anthos meaning flower.
The common name of pink for plants in the genus Dianthus is in probable reference to the fringed flower petal margins (they appear to have been cut with pinking shears) and not to flower color.
‘Siskin Clock’ is a perennial dianthus that is noted for its compact habit, distinctive flowers and long flowering period. White flowers with dark burgundy red eyezones and petal edges bloom somewhat profusely atop a loose mound of gray-green leaves typically growing to 7” tall. Flowers bloom from June to July with sporadic additional bloom into late summer. This cultivar was introduced by John Whetman of Devon, England. Some confusion currently exists in commerce as to the proper cultivar name for this plant.
Problems
Carnations are susceptible to a variety of fungal, bacterial, and viral pathogens, including botrytis, rust, powdery mildew, leaf spots, and fusarium wilt. They are also susceptible to aphids, caterpillars, leafminers, spidermites, and scale. All these pest and disease issues are greatly exacerbated when carnations are grown under glass for cut flower production, and are less problematic when grown outdoors in a garden bed. Deer tend to avoid this plant.
Uses
Rock gardens, beds, border fronts, edgings, and containers. When massed, the foliage can form an attractive ground cover.