Osteos at UGA Gardens in Athens, GA

Osteospermums (Osteospermum x hybrida ) are members of the daisy (Asteraceae) family, commonly called African Daisy, Blue-eyed Daisy, or Cape Daisy. Osteos are cool season annuals that excel in northern and less so in southern U.S. gardens. Osteos bloom more profusely in full sun, but want some cooling relief during the summers.

Osteos have always been a popular cutflower, but are now becoming a annual bedding plant. They should be planted early with petunias and million bells (Calibrachoa). The heat of summer knocks osteos out of bloom, but they often recover to bloom again in late summer. Keep them adequately watered the first month after planting.

Flat daisy-like petals radiate out in a tubular or spoon shape. Every year new color choices continue to win over gardeners. Plant breeders are improving summer heat-tolerance and introducing more compact growing cultivars. Color choices abound from lavender, pink, white, yellow and bi-color, with more introduced every year. Their dark green foliage may vary with the cultivar from lance- , ovate, and/or lobed- shaped.

They prefer an acidic soil, but perform well between 5.5 to 6.5 pH. Feed osteos on a bi-weekly basis with a water soluble fertilizer such as Miracle-Gro™, Jack’s™, or Schultz™ according to package directions. Although drought tolerant once established, osteos need one inch of water weekly to look their best.

During periods of intense heat and drought, growth slows or plants go dormant. Cut osteos back in late summer to stimulate new stems and leaves. Remove wilted flowers and old worn foliage to induce new flowering.

Osteos are super performers in hanging baskets and window boxes. Cultivar series vary from 12 – 36 inches in height by 12 – 24 inches in spread. Among the popular osteos are the Voltage®, 3D®, and Margarita® series.