Crassula barbata white flowers all the way up

Numerous, small and white Crassula barbata flowers are open in the spaced clusters of this inflorescence. The sturdy, cylindrical flower stem has elongated more among the lower clusters, showing smooth, bare patches, dull yellowish in colour.

In racemes where flowers are spaced singly up the stalk, the upper ones in many species open last. Here there is floral sequencing within clusters, open flowers still present in the lowest groups, while some already flower right at the top (iNaturalist).