Here are two of the six known species of the genus Fockea, an African vine that has a warty caudex. There are only a couple of differences in these two Fockea species; the F. edulis has smoother leaves than the F. capensis, and the caudex of the F. capensis is more warty. Some believe that F. capensis, also known as F. crispa, is not a separate species, but just a variety of the F. edulis. The unusual, bumpy caudex makes these plants popular with caudiform collectors, who like to keep the warty caudex as exposed as possible for looks. Keeping the caudex exposed is another way to prevent rot.
These vines are easy to grow, only requiring some water in summer and not much in winter, as they are rot-prone. I keep my two vines in the house in winter in order to preserve the vines, as these plants are semi-deciduous. In Phoenix, they require light shade in the summer, so I keep them on the patio. The caudex cannot take direct sun, as it is prone to sunburn, so I can't place these caudiforms in my garden. If and when they bloom, they flowers will be green and lightly fragrant.
The caudex can grow to two feet in diameter, and at one time, it was a common food source for the African tribe, the Hottentots. Cooking the tuber prior to eating it was necessary in order to deactivate the alkaloids found there. The Latin word, edulis, means edible.