Osteospermum, commonly known as the African Daisy or Cape Daisy, is a genus of flowering perennials belonging to the Asteraceae family. Native to South Africa, these plants have been enthusiastically adopted into American horticulture primarily for their exceptional and prolonged blooming period. While technically tender perennials in USDA zones 9-11, they are most widely cultivated as annuals across the vast majority of the United States. Key species and hybrids, such as Osteospermum ecklonis and the prolific ‘Serenity’ and ‘Sunscape’ series, offer a diverse palette of flower colors including pristine white, vibrant purple, soft pink, and sunny yellow, often with striking contrasting centers.
The primary ornamental feature of Osteospermum is its daisy-like composite flowerhead, which possesses a unique characteristic: its petals (ray florets) often close at night or during overcast weather, reopening with the sunlight. This phototropic response adds a dynamic, living element to the garden. The flowers are prolific, creating a dense carpet of color from spring until the first hard frost. The foliage, typically a lush, deep green with a slightly succulent quality, forms a dense, low-mounding habit that serves as an attractive backdrop even when fewer blooms are present. This combination of vibrant, long-lasting flowers and neat foliage provides immense aesthetic value in designed landscapes.
To thrive in the American landscape, Osteospermum has specific cultural requirements. It demands full sun exposure; a minimum of six to eight hours of direct sunlight is crucial for abundant flowering and maintaining a compact growth form. Well-drained soil is non-negotiable, as the plant is highly susceptible to root rot in heavy, waterlogged clay soils. It performs excellently in raised beds, containers, and sandy soils. Osteospermum is notably drought-tolerant once established, making it a superb choice for water-wise xeriscaping projects in drier regions. While it appreciates occasional watering during extreme heat, its overall low water requirement aligns with sustainable gardening practices.
The growth habit and cultural needs of Osteospermum make it incredibly versatile in design. Its low, spreading form (typically 12-18 inches tall and wide) designates it as a perfect candidate for the front of borders and beds, where it can spill over edges and soften hardscapes. It is a premier choice for container gardening, including patio pots, window boxes, and hanging baskets, providing season-long color cascades. Mass plantings create a dramatic, uniform swath of color that is highly effective in commercial landscapes and public parks. Furthermore, it is an excellent groundcover for sunny, sloped areas where erosion control and low maintenance are desired.
Osteospermum integrates beautifully with other sun-loving annuals and perennials. It complements the vertical forms of Salvia and Veronica, contrasts beautifully with the fine textures of ornamental grasses like Blue Fescue, and pairs elegantly with other drought-tolerant species such as Lavender, Russian Sage, and Sedum. While not a top-tier native pollinator plant, the open flower form does attract a variety of beneficial insects, including bees and butterflies, adding to the ecological value of the garden space. Its deer and rabbit resistance is another significant advantage for gardeners in areas plagued by these herbivores.
