Crassula multicava subsp. floribunda
on 22nd June 2012
Crassula multicava subsp. floribunda in the Krantzkloof Nature Reserve inland of Durban.
Crassula multicava subsp. multicava is well known in cultivation, but subsp. floribunda is less so. My experience of the taxa is that subsp. multicava begins to occur from the Mzimkulu River southwards and occurs in a variety of rocky to stony habitats, often semi-open and even somewhat disturbed. Crassula multicava subsp. floribunda is mainly distributed to the north, from about Eston to north of Durban. It is more of a habitat specialist, occurring in dry to mesic Scarp Forest in Natal Group sandstone gorges, on south-facing aspects of cliffs or sometimes on shaded basement granites that occur beneath the sandstone, in the river-eroded gorge bottoms. SANBI nonetheless shows a wider distribution than this for Crassula multicava subsp. floribunda, into the Eastern Cape, but I am not sure this is right and was never mentioned by Toelken.
Although recognized as subspecies, having seen the taxa many times in the field and growing them, they are not so alike, except for the similarly-shaped, pitted leaves and it may instead be that two species are involved. Subsp. floribunda has much thicker stems than subsp. multicava. Toelken mentions 3 mm versus 6 mm, but I have frequently seen stems up to about 10 mm. Plants are also often hairy. The flowers in subsp. multicava are usually in fours, with smaller petals that are often pinkish, whereas in subsp. floribunda they are in fives, lager and always white. Crassula multicava subsp. floribunda also does not produce adventitious buds in inflorescence bracts as subsp. multicava does.
Subsp. multicava works well as a ground cover, but subsp. floribunda is not particularly successful out of a pot.