For stunning, vibrant color, it's hard to beat this South African native. Slim yet sturdy stems, up to 1 feet tall, emerge from clumps of tongue-shaped, lobed leaves. The 4- to 5 inches daisies, borne one to a stem, fairly glow in colors of red, orange, coral, pink, yellow, and cream. The basic form features a single ring of petal-like rays surrounding a prominent central disk. Hybrid forms may display two rows of long rays or an outer ring of long rays and an inner ring of short, tufted ones; or they may be fully double with a fluffy look.
Many strains are available, including types with dark centers and dwarfs just 6 inches tall. Where gerberas are perennial, they can bloom at almost any time of year, unless frost kills them to the ground. In this case, they'll sprout from underground stems in spring and begin blooming shortly afterward.
Outside the Coastal and Tropical South, they're traditionally treated as annuals. Plants in the Jaguar (810 inches tall) and Royal (1014 inches tall) series are early, dependable bloomers.
The strains below have proven hardy into the Middle and Lower South as well; USDA 7-11. Wolfpack Country, bred at North Carolina State University, will bloom continuously from spring until frost. Hybrids in the Drakensberg Daisy series produce many medium-size blooms in the full color range on stems 810 inches tall; vigorous, long-blooming, and tolerant of humidity. Top performers in the Garvinea series are light orange 'Orangina' and deep orange 'Jilly'. Keep them well-watered in full sun. For part sun and containers, try the large-flowered Patio series.
Gerberas need excellent drainage; if your soil drains poorly, plant in raised beds. Space about 2 feet apart, with root crowns at least 12 inches above soil level. Feed monthly with a balanced liquid fertilizer. Pick off old, yellow leaves. Water deeply and let soil become nearly dry before watering again. Divide (in late winter) only when clump is crowded and flowering declines. When cutting flowers for arrangements, slit the bottom inch of stem before placing in water.
Most people start with trans- plants, but you can also grow gerberas from seed. Seed must be fresh to germinate well. Sow in moist potting soil; keep air temperature at about 70F. Water carefully. Seed may take several weeks to sprout. Seedlings flower in 4 to 6 months.
Powdery mildew can be a problem when humidity is high and temperatures are moderate. Crowded plantings and shade makes the problem even worse. The best defense is to start with disease-free plants and to choose the newer, more disease-resistant selections. If a chemical control is needed, consult your local Cooperative Extension Office for a recommendation.