How to Grow Cape Daisy From Seed

Cape daisy is a warm-season flower with a long runway from seed to bloom, so start it early. Sow indoors about 6 to 8 weeks before your last spring frost, then move plants out once nights hold above 40F and the danger of frost has passed. In frost-free zones 10 and 11 you can also direct-sow into warm soil in spring. Because it takes 10 to 16 weeks to flower, an indoor head start is what gets you color by early summer rather than late in the season.

Osteospermum seeds need light to germinate, so do not bury them. Press the small tan seeds onto the surface of moist, well-drained seed-starting mix and cover with only a dusting, about a sixteenth of an inch, of fine vermiculite. Keep the mix around 65 to 70F and lightly moist, and seedlings usually appear in 10 to 21 days. Once each seedling has two sets of true leaves, pot it on, harden it off, and transplant outside 12 to 18 inches apart in full sun and free-draining soil.

Give cape daisy full sun and soil that drains well and it mostly looks after itself. Water regularly while young, then ease off, since established plants are drought tolerant and rot in soggy ground. A light monthly feed keeps the flowers coming. Climate really shapes how you grow it: in hot, humid regions like Florida and the Gulf Coast it flowers best in the cooler shoulder seasons and can stall in midsummer heat, while in mild-summer areas like coastal California and the Pacific Northwest it blooms steadily for months. Across the North and Midwest, treat it as a summer annual and enjoy it from the last frost until the first one returns.

Cape daisy pairs well with other sun-loving, pollinator-friendly flowers that enjoy the same lean, well-drained soil. These four make especially good neighbors in a border or a big container, and you can add any of them in one click:

Cape daisy is grown for its flowers, so care here means keeping the blooms coming. Deadhead often: follow each spent flower down to the first set of leaves and cut the whole stem, which stops the plant setting seed and pushes fresh buds. Pinch young plants once to make them bushier, and cut a few stems for the vase when the blooms are just opening. In zones 10 and 11 a light trim after the main flush encourages a second wave.

Cape daisy earns its space as a pollinator plant and a long-blooming source of color. The open, daisy-shaped flowers give bees and butterflies an easy landing pad through the warm months, so a drift of them lifts a whole border. It thrives in containers and hanging baskets, edges a path with tidy mounds of color, and holds up well as a cut flower, opening in the sun and closing at dusk. Because it shrugs off heat and drought once settled, it is a reliable pick for water-wise beds and sunny front-yard plantings.

• Seeds will not sprout: they need light, so surface-sow and barely cover them, keep the mix at 65 to 70F, and be patient, since germination can take up to three weeks.
• Flowers closed during the day: too little light. Move the plant to a spot with at least six hours of direct sun and the blooms will open.
• Few flowers and leggy growth: usually not enough sun or missed deadheading. Grow in full sun, pinch young plants, and remove spent stems.
• Yellowing, wilting plants: often overwatering or heavy soil. Plant in free-draining ground or pots and let the top inch dry out between waterings.