August 1996
Even if you need to restrict your landscape water use this summer, you don't need to restrict using colorful flowers. Home landscapes can be awash with color and fragrance by using annuals. There are several heat- and drought-tolerant plants that thrive in hot, dry conditions.
Madagascar periwinkle or vinca Catharanthus roseus is one of the most heat-tolerant annuals available. The lush, dark-green foliage is somewhat glossy and forms 2-foot-tall mounds in full sun. The flowers are a variety of colors including pink, purple, white and bicolors.
Celosia or cockscomb Celosia argentea plumosa or C. argentea cristata is unique for its unusual, feathery flowers of bright pink, red, yellow, and orange. Plants may grow from 6 inches to 4 feet tall, depending on the cultivar. Celosia is an excellent cut flower, fresh or dried.
Spider flower Cleome hasslerana can reach 6 feet in height in full sun. The unique, spider-like flowers are violet, rose, or white. Cleome, though an annual, is a reliable reseeder and should return yearly.
Threadleaf coreopsis Coreopsis verticillata is a perennial that grows 18 to 30 inches in height. Its yellow, daisy-like flowers survive the driest of conditions. 'Moonbeam' is an All-America Selections winner with light-yellow flowers. A pink cultivar 'Rosea' also is available.
Globe amaranth Gomphrena globosa blooms in a variety of bright colors, including red, rose, pink, and purple. Dwarf cultivars are available, as well as taller ones that may reach 2 feet in height. Globe amaranth makes a wonderful dried flower.
Morning glory Ipomoea tricolor is an annual vine that should be grown from seed; garden centers rarely stock morning glory plants. This vigorous vine can reach 8 to 10 feet tall and requires a trellis or vertical support. The delicate-looking flowers open in the morning and close in the afternoon. Morning glory is available in white, blue, pink, and red.
Gold medallion Melampodium paludosum is highly underused in the landscape. This annual plant covers the ground with lush, green foliage, dotted with small, yellow, daisy-like flowers. Gold medallion forms low mounds in the landscape and flourishes in full sun.
Moss rose Portulaca grandiflora has fleshy, succulent foliage that is unusual for an annual plant. Don't let the delicate-looking flowers deceive you; this plant craves the heat of summer. The brightly colored flowers (including bright scarlet, pink, fuchsia, and orange) close at night and reopen as soon as the sun hits them.
(Originally published as "Annuals for Hot, Dry Summers," by Ellen S. Bennett, Horticulture Extension Technician, Virginia Tech, in The Virginia Gardener Newsletter, Volume 12, Number 7.)