HARDINESS: Zones 3 to 8
PREFERRED SOIL pH: Neutral to slightly alkaline
PREFERRED SOIL TYPE: Well-drained
PREFERRED LIGHT: Sun
ATTRIBUTES: Fragrant flowers and low, grasslike, gray-green foliage; for beds, edging
SEASON OF INTEREST: Flowers in spring; evergreen foliage in mild-winter climates
FAVORITES: 'Bath's Pink', 'Mountain Mist', 'Essex Witch', 'Zing Rose', 'Brilliant'
QUIRKS: Wet soil in winter leads to fatal root rot
GOOD NEIGHBORS: Candytuft, iris, salvia, thyme, veronica
WHERE IT GROWS BEST: Sun and well-drained, neutral soil
POTENTIAL PROBLEMS: Root rot and fungal diseases in high humidity or poorly drained soil
RENEWING PLANTS: Lives for years if crowded clumps are thinned or divided every few years
CRITTER RESISTANCE: Excellent
SOURCE: Bedding plants; division: late summer or spring
DIMENSIONS: 6-24 in (15.2-61 cm) tall, 8-16 in (20.3-40.6 cm) wide
Dianthus in the Landscape
It's easy to fall in love with dianthus. You may be charmed by the fragrance, silvery foliage, or simplicity of the blossoms. Fortunately, the plants that boast these features are easy to grow.
Dianthus need good soil drainage, which makes these low-growing plants a natural for rock gardens and crevices in stone walls. They look superb edging the front of a border or spilling over a concrete curb in the company of candytuft or thyme. Pink-flowered types are usually easy to mix with other spring-blooming perennials. Once the bloom period passes in late spring, you have a groundcover of fine-textured, gray-green foliage that blends with all plants.
Cottage, Cheddar, and Maiden Pinks
Often called pinks because the zigzag petal edges appear to have been cut with pinking shears, dianthus include dozens of named cultivars of confusing lineage. These cultivars are now sorted into groups rather than by species. The cheddar pink types offer spicy fragrance and tight blue-gray foliage that often persists year-round. Cultivars such as 'Bath's Pink", for Zones 7 to 8, and the more cold-tolerant 'Mountain Mist' bloom light pink in spring and make a fine edging or ground cover.
Cottage pinks also have a spicy fragrance, and though their foliage is not as fine and grasslike as that of
the cheddars, their bloom time is longer. Deadheading, or removing spent blooms, will extend flowering even longer.'Essex Witch' produces rose pink flowers, and there are many others with flowers of varying shades, some with double flowers. Cottage pinks grow 12 in (30.5 cm) tall.
Petite maiden pinks offer no fragrance, but they bloom for a long period if trimmed often. Cultivars, such as the rose red 'Zing Rose' or deep pink 'Brilliant', are dependable from Zone 3 to 6 but often need replacing after 2 years in the heat and humidity of Zones 7 and 8, even when deadheaded regularly.
Provide dianthus with sun and well-drained, slightly alkaline soil. Work in a modest amount of organic matter at planting time, and in acid soil, add garden lime according to package directions to raise the pH to nearly neutral. You can also mulch around plants with limestone pebbles, which will continuously contribute lime to the soil. Discourage fungal leaf diseases and root rot by planting where air circulation and soil drainage are good. Withhold nitrogen fertilizers or your plants will produce leaves at the expense of flowers. Pests are few, but occasional sap-sucking insects, such as aphids or spider mites, which are spider relatives, can be dislodged with a strong spray of water or treated with insecticidal soap per label directions.
Rejuvenate clumps every 2-3 years, a necessary step to relieve crowding, which in turn invites fungal diseases. In late summer or early spring, use a sharp knife and a trowel to cut out and lift the oldest crowns from the center of the clump. Throw the old plants away. Fill the holes left behind with a mixture of compost and sand, and the surrounding plants will spread out to quickly fill the gap. You can also increase your supply by cutting small divisions from a clump and replanting them within a few days, where you want them to grow.