Ceropegia contains a diverse group of 160 named species distributed over a wide range including the Canary Islands, Africa, Madagascar, Arabia, India, Ceylon, China, Indonesia, Phillipines, New Guinea and Australia (Queensland).
Some of these perrenial plants have succulent stems, which may be dwarf or vine-like and posess fibrous roots, while others have tubers and relatively thin stems, along which new tubers may form in some species. Species with fleshy thickened roots are the most difficult to grow. The leaves are opposite, but may be vestigal on species with succulent stems.
Flowers occur either singly or in umbel-like clusters and have a tubular corolla 2 or more times as long as its diameter and longer than the 5 lobes. The base of the tube is usually inflated and the tube may have downwardly orientated hairs on the inside and hairs on the outside and at the edges of the lobes. Colours include reds, purples, yellows, greens and mixtures of these. Flies entering the corolla may become trapped by the hairs until the flower wilts. The tips of the lobes are fused together to form a cage-like flower structure in many species, but are open in others.
Cultivation of Ceropegias
A gritty compost is suitable, and clay pots help with drainage, especially for the species with white thickened roots which are the most susceptible to rotting and for species forming large tubers. Ceropegias appreciate water and a little fertiliser during warm weather, although some care with watering is required for the more difficult species. The vine-like species can suffer from prolonged drought.
Typically, many of these species grow and climb naturally among bushes which provide shade and humidity to the base, while the vegetative growth is in the light. Where tubers occur, they are best planted on the surface of the compost, and the vegetative growth allowed to twine around supports or to trail down from a hanging pot. The latter mode of growth has the advantage of not using valuable bench space. Small tubers formed at joints in the thin stems of some species can be used for propagation. If the tuber rots or dries out, don't panic. As long as some of the top growth is still in reasonable condition, it may be possible to save the plant by re-rooting stems in damp gravel.
In the more succulent species, stems layered on the compost will produce roots from their lower surface, and climbing reproductive flowering shoots which can be allowed to hang down or twine around supports. Vine-like species readily root from cuttings inserted vertically in the soil to the bottom of a pair of leaves. A minimum over-wintering temperature of 10°C is adequate providing the plants are kept dry.