You'll find more information with with spelling Dymondia margaretae.
"Fast
growing, the silver carpet forms a neat, prostrate, fairly drought-resistant ground cover, with blue-grey foliage and small, yellow, daisy-like
flowers [in
spring]. If not given a well-drained position the
plant tends to rot and die back. It could also be used to form a ground cover between paving stones or railway sleepers.
plant the silver carpet in light, sandy, well-drained soil, adding plenty of compost. Do not overwater. Propagation by
seed or division of clumps. Natural distribution: it grows in the southern Cape [of South Africa]."