This plant looks very much like Arctotheca populifolia, the leaves being about the same, but its flowers have small white ray florets as can be seen on the photo. A. populifolia has yellow florets. This is then probably a different species, but the leaves and growth habit suggest that it may belong to the Arctotheca genus. The plant list of the De Hoop Nature Reserve where this photo was taken, does include an Arctotheca species, yet unidentified.
A. populifolia is a common species that grows well on sandy beach areas all along the coast from the west of the country to the east coast and up to Mozambique. The name indicates the similarity of its leaves to those of poplar trees.
The plant is reported to have escaped and invaded land widely in at least Australia, where it is described as naturalised (Manning, 2007; www.ubcbotanicalgarden.org).