Plant Highlight: Astridia alba
Astridia is a small genus of shrubby plants in the Ice Plant Family (Aizoaceae), native to the northwestern corner of South Africa and adjacent southwestern Namibia. This area is at the northern end of the winter rainfall zone, where rain is scarce and erratic. Since plants in this genus are little known in cultivation, their horticultural needs are uncertain, but coastal areas in central and southern California seem like promising places to try them because of the prevailing dry summers.
At the Ruth Bancroft Garden, we have had Astridia alba planted out for the past year and a half, and it has done very well. It is a small shrub, eventually reaching a height of about 1½ feet (50 cm), with leaves that look like pallid stubby fingers. In nature, it is found near the mouth of the Orange River, which is the border between Namibia and South Africa. Its flowering period is in fall and early winter. The white flowers emerge a few at a time, rather than completely covering the plant in an intense burst of flowering as is seen in some other ice plants
Some references list Astridia alba as a white-flowered variant of Astridia longifolia, which otherwise has red flowers.