The snowy white clusters of Wild Rosemary, Eriocephalus africanus.
Evening-scented Gnidia squarrosa. This dainty yet hardy shrub has proven to be a reliable filler where plants have died from poor drainage. I first saw this species growing wild in a seasonal wetland in Vermaaklikheid - and indeed it seems to tolerate wet feet, or even thrive under these conditions.
And there's lots, lots more. If you haven't been to visit the Biodiversity Garden lately, it's a good time to visit.