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Osteospermum - Growing Guide
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Osteospermum - Growing Guide

African daisy

Osteospermum are generally regarded as summer bedding plants that will not survive a normal winter and this is certainly true of many of the gaudier and newer varieties which are so numerous in all garden centres in the summer. However Osteospermum ‘Cannington Roy’ and O. ecklonis compacta will withstand short periods of -10°C and can be considered fully hardy garden plants. Most other Osteospermum should be regarded as half hardy annual plants which may survive a mild winter.

Osteospermum are ideal plants for containers and window boxes as well as for the edges of borders because they flower continuously from late spring to autumn. By regularly removing their dead daisy flower heads you will encourage this process while the plant grows exponentially. So exponentially in fact that many become straggly and misshapen by the autumn and are often then only fit for the compost bin. Cutting them back hard in the autumn may work with some varieties in sheltered areas but few will shoot again properly next spring and it is best to start again then with new young plants.

Osteospermum will grow well in any moderately fertile, warm site in full sun. They need good drainage as they will rot off if waterlogged. It is very easy to take your own new growth cuttings in the summer and root them with a little bottom heat in the greenhouse. Pot on the rooted cuttings before autumn and keep them in frost free conditions ready to plant out gain in the spring. In the greenhouse beware of aphids and ensure good ventilation over winter to avoid powdery mildew attacks.

O. ecklonis compacta has a spreading compact habit and is suitable for growing on banks of rockeries. O. ‘Cannington Roy’ and O. ‘Tresco Purple’ are more upright in habit and will grow to about 18-24in in height with a similar spread.