Osteospermum, commonly known as African Daisy, is a genus of flowering perennials prized for their vibrant, daisy-like blooms and remarkable resilience. Native to South Africa, their success in the diverse climates of the United States hinges on selecting varieties bred for specific regional challenges, particularly winter hardiness and heat tolerance. Understanding their basic plant requirements is key: they thrive in full sun and well-drained soil and are generally tolerant of coastal, windy, and drought-prone conditions once established.
The cool, moist winters and mild summers of the Pacific Northwest are ideal for many Osteospermum cultivars. The primary concern here is ensuring good drainage to prevent root rot during wet winters. The **'Serenity' Series** is an excellent choice, offering a wide range of colors from white to deep purple. These plants are compact, flower prolifically, and are well-suited to the region's climate. Another top performer is **Osteospermum '4D Pink'**, known for its unique "spooned" petals and striking two-tone pink flowers. It provides a long blooming season from spring through fall in the region's temperate conditions.
Gardening in the South and Southwest demands plants that can withstand intense heat and prolonged sun exposure. For these regions, heat-tolerant hybrids are essential. The **'Soprano' Series** is specifically bred for superior performance in summer heat, maintaining vibrant blooms in shades of purple, lavender, and white when other varieties might falter. Similarly, the **'Voltage' Series** is renowned for its vigorous growth and large flowers that stay open longer, even on overcast days—a common trait sought after in Osteospermum. These varieties are often treated as perennials in zones 9-10 and as annuals elsewhere.
In these regions with colder winters, Osteospermum is primarily grown as a colorful annual for spring and fall containers and gardens. The key is to select early-flowering and cold-tolerant types. The **'Sunscape' Series** is a standout, known for its ability to bounce back from light frosts and produce flowers earlier in the spring. Varieties like **'Sunscape Cosmic'** offer beautiful bicolor flowers. For a reliable show, the **Astra™ Series** is another excellent choice, forming dense mounds covered in flowers that are more tolerant of cooler temperatures common in the spring and autumn months in these zones.
California's dry-summer climate mirrors the native conditions of Osteospermum, making it an ideal plant for water-wise landscapes. Here, they can be treated as evergreen perennials. The **'Zion™' Series** excels in these conditions, producing large, stunning flowers in brilliant blue, copper, and yellow. Its robust nature makes it perfect for slopes and borders. For a more trailing habit ideal for containers and hanging baskets, **Osteospermum 'Pink Whirls'** is a fantastic selection. Its intricate, spoon-shaped petals add textural interest to the garden and it thrives in the full sun and well-drained soils characteristic of the region.
