Gomphocarpus physocarpus flowers and buds in rings

These white-and-cream flowers of the balloon milkwood, proper name Gomphocarpus physocarpus, were photographed in the Walter Sisulu National Botanical Garden during May.

A second developing cluster is nodding above the open flowers. It comprises pale green, globose buds, ridged where the corolla lobes will soon part and spread in the opened flowers. The five pointed, in-curving corolla lobes of each flower form a base for the boat-shaped corona lobes, positioned in a second ring in the centre above the corolla. Right in the middle there is a third ring. The tiny, yellow style head with five rounded lobes completes this third concentric ring, each ring made up of five parts. The five tiny sepals of the calyx behind the corolla that constitute a fourth ring on the outside.

Look for the rings in other Gomphocarpus flowers (https://pza.sanbi.org).