This genus is made up of more than 300 species and an extremely large number of hybrids. Most kinds form attractive evergreen mats or tufts of grasslike green, gray-green, blue-green, or gray-blue leaves. Single, semidouble, or double flowers come in white and shades of pink, rose, red, yellow, and orange. Many have a rich, spicy fragrance. The main bloom period for most is spring into early summer, but some kinds rebloom later in the season or keep going into fall if faded flowers are removed.
Among dianthus are favorites such as cottage pink and sweet William, highly prized cut flowers such as carnation (clove pink), and rock garden miniatures. There are hundreds of varieties and hybrids available, including some local favorites.
All kinds of dianthus thrive in light, fast-draining soil. Carnations, sweet William, and cottage pinks need fairly rich soil. Rock garden or alpine types require a gritty growing medium, with added lime if soil is acid. Avoid overwatering. Sow seeds of annual kinds in flats or directly in the garden. Propagate perennial kinds by cuttings made from tips of growing shoots, by division or layering, or from seed. Carnation and sweet William are subject to rust and fusarium wilt.
Vigorous biennial often grown as an annual. From southern Europe. Grows to 20 in. high and 1 ft. wide, with sturdy stems. Leaves are flat, light to dark green. Dense clusters of white, pink, rose, red, purplish, or bicolored flowers, about 1/2 in. across, set among leafy bracts; not very fragrant. Sow seeds in late spring for bloom the following year. Double-flowered and dwarf strains are obtainable from seed. Indian Carpet is only 6 in. high. The Amazon series grows to 18–36 in. high.
This perennial is a highly bred Mediterranean species. Two distinct categories exist: florists’ and border types. Both have double flowers, bluish green leaves, and branching, leafy stems that often become woody at base.
Border carnations are bushier and more compact (12–14 in. high and wide) than florists’ type. Fragrant, 2–2 1/2-in.-wide flowers are borne in profusion. Effective as shrub border edgings, in borders of mixed flowers, and also in containers. Hybrid carnations grown from seed are usually treated as annuals but often live over. ‘Juliet’ makes compact, foot-tall clumps and bears 2 1/2-in. scarlet flowers over a long season; ‘Luminette’, 2 ft. tall, is similar. Pixie Delight strain is also similar but includes full range of carnation colors. Knight series has strong stems, blooms in 5 months from seed. Bambino strain is a little slower to bloom. There is also a strain called simply Hanging Mixed, with pink- or red-flowered plants that sprawl or hang from pot or window box. Newer varieties include bright red ‘Cinnamon Red Hots’, to 1 ft. tall; rose pink ‘Pinkie’, reaching 6 in. high; and foot-tall ‘Velvet ’n Lace’, with frilly dark red flowers edged in white.
Florists’ carnations are grown commercially in greenhouses, outdoors in gardens in mild-winter areas, including higher-elevation gardens in Hawaii. Greenhouse-grown plants reach 4 ft., have fragrant flowers 3 in. wide in many colors—white, shades of pink and red, orange, purple, yellow; some are variegated. For large flowers, leave only terminal bloom on each stem, pinching out all other buds down to fifth joint, below which new flowering stems will develop. Stake to prevent sprawling. Start with strong cuttings taken from the most vigorous plants of selected named varieties. Sturdy plants conceal supports, look quite tidy.
Biennial or short-lived perennial; most varieties are grown as annuals. Erect plant to 6–30 in. high and 6–10 in. wide; stems branch only at top. Stem leaves are narrow, 1–3 in. long, 1/2 in. wide, hairy on margins. Basal leaves are usually gone by flowering time. Flowers are about 1 in. across, rose-lilac with a deeper-colored eye; lack fragrance.
Modern strains are compact domes (1 ft. high or less) covered with bright flowers in white, pink, red, and all variations and combinations of those colors. Petals are deeply fringed on some, smooth-edged on others. Some flowers have intricately marked eyes. ‘Fire Carpet’ is solid red; ‘Snowfire’, white with a red eye. Telstar is a bushy, extra-dwarf (6–8 in.) strain with dark green leaves. Sow directly in ground in spring, in full sun, for summer bloom. Pick off faded flowers with their bases to prolong bloom.
From Europe and Asia. Grows to 8–12 in. high, forming a loose mat to 1 ft. wide. Blossoms, about 3/4 in. wide with sharp-toothed petals, are borne at ends of forked flowering stems with short leaves. Colors include white and light or dark rose to purple, spotted with lighter colors. Blooms in summer, in just a few weeks from seed; sometimes again in fall. Useful, showy ground- or bank cover. Can tolerate half-day shade.
Perennial, from Europe. Neat, ground-hugging, foot-wide mat of blue-gray foliage. Stems 6–10 in. high bear small, typically pink to rose, single blossoms (less than an inch across) that are very fragrant. Bloom season lasts from spring to fall if plants are deadheaded regularly. Effective as a groundcover or edging or in a rock garden.
Charming, almost legendary European species, cultivated for hundreds of years and used in developing many hybrids. Typically has loosely matted gray-green foliage in a clump to 2 ft. wide. Flowering stems grow to 10–18 in. high; spicily fragrant, dark-centered flowers in rose, pink, or white, with more or less fringed petals. Highly prized are old laced pinks, with white flowers in which each petal is outlined in red or pink. Cottage pinks bloom from summer to fall if deadheaded. Indispensable edging for borders or for peony or rose beds. Perfect addition to small arrangements and old-fashioned bouquets. Choice selections include ‘Essex Witch’, with semidouble, rose-pink flowers on 5-in. stems; ‘Sweetness’, with a mix of darker-centered shades on 4-in. stems; and ‘Musgrave’s Pink’, a foot-high classic that’s at least 200 years old and bears intensely fragrant, single white blooms with a green eye.
Warm-season vegetable from tropical Asia. Large, erect, bushy plant to 6 ft. tall, with big, bold, dee...
Native to tropical America (mostly Mexico). Showy summer- and fall-blooming plants, open and branching...
From Central America. This annual has white, pink, lavender, or purple flower heads on 1–2-ft. s...