Culture
Winter hardy to USDA Zones 10-11. In St. Louis, plants are grown as annuals in average, loose, moderately fertile, evenly moist, well-drained soils in full sun. Plants generally dislike hot and humid summers. Purchase new plants in spring or plant seed cultivars indoors about 6-8 weeks prior to last spring frost date. Deadhead spent flowers to prolong bloom.
Noteworthy Characteristics
Osteospermum is a genus of about 70 species of subshrubs, herbaceous perennials and annuals. They are native to southern Africa and the Arabian Peninsula. Many of the plants sold today under the names African daisy or osteospermum are cultivars and hybrids derived from O. ecklonis, O. jucundum and several other species. As a group, these plants are frost-tender subshrubs or herbaceous perennials that feature daisy-like flowers on upright stems rising to 1-3’ tall. Stems are clad with lanceolate green leaves having entire, lobed or toothed margins. Each flower features a center disk of tiny tubular flowers surrounded by fertile, petal-like ray flowers in a variety of colors including shades of white, pink and yellow. In cool summer climates, flowers bloom freely from spring to fall frost. In hot summer climates, flowers bloom well in spring to early summer, but decline rapidly with the onset of consistently hot summer temperatures. Fruits are seed-like achenes.
The genus name Osteospermum comes from the Greek osteo meaning "bone" and sperma meaning "seed" in reference to the hard seeds.
'Wildside' was bred by Masao Kanno of Chigasaki, Japan from a series of crosses using several hybrids of Osteospermum fruticosum. It is a perennial but is not hardy in the St. Louis area. 'Wildfire' has rosy-purple ray flowers and violet to blue disk flowers and unlike the species plant, its flowers will remain open in low light. It has a dwarf, broad-spreading habit, spatulate green leaves with widely toothed margins and grows 1/2 to 1 ft. tall and wide. U.S. Plant Patent PP#10,603 issued September 15, 1998.
Problems
No serious insect or disease problems. Watch for aphids. Mildew and verticillium wilt may occur.
Uses
Beds and borders. Containers.