Sometimes known as South African sailor boy daisies, these shrubby perennial plants grow to a height of between 30cm and 1m. The simple daisy blooms open when the sun is shining, and their main flowering season is winter and spring. They are tough, drought-tolerant plants and do best in poor, dry, well-drained soil in full sun. They will actually not perform well if the soil is rich and well watered!
Modern named types are more compact than the original rather sprawling ones, and yellow and orange versions have been added to the traditional pink, white and purple flower range, though these old ones are probably the toughest performers. The newer types only seem to last one season, in my experience, so are best regarded as annuals. Most have dark blue centre to their flowers, which in the case of the sparkling whiter-than-white form gave rise to the common name of 'sailor boy' as they do have a distinctively naval look. There is a white version with a pale centre, which is attractive. There are also a couple of forms with unusual crimped petals. They do have a tendency to self-seed so should be grown with caution near bushland areas and cut back hard after flowering. They may exhaust themselves after a few years, when they should be replaced with a softwood cutting taken in spring. In general, I tend to treat them as an annual these days, planting out a few established potted plants in autumn to enjoy over winter and spring, then composting them!
They combine well in the garden with other plants which enjoy sun and well-drained soil and which bloom in spring, such as Coleonema, marguerite daisies, lavender, wallflowers, and Euphorbia species and cultivars. The more compact sorts can be grown in a large container in a sunny spot.