From 'gompho', nail, and 'carpus', fruit; for its spiny seed pods, this genus, in the subfamily Asclepiadinae is closely allied to Asclepias, from which a number of species were recently transferred. Broadly speaking, the genus Asclepias is maintained for the species growing in the Americas, whilst those species in Africa and Arabia are transferred to Gomphocarpus. With the exception of Gomphocarpus brevipes all of the species listed can be grown outdoors as hardy perennials however in northern Europe it would be wise to grow them in tubs and over winter them in greenhouse conditions where they should be watered sparingly.
Grown from seed collected in Botswana by Alice Beamond this species is atypical of Gomphocarpus in having a caudiciform root and a flower structure totally different to any other species pictured here. As the species name indicates it is low growing with short slender stems and long narrow grass like leaves.
Grown from seed personally collected at Gannabos, off the R355, SE of Loriesfontein, Northern Cape Province in 31-Aug-2000 this species forms small bushes with thick leathery leaves and produces spiny seed pods typical of the African Gomphocarpus species.
Native throughout Africa, from Ethiopia and Mediterranean north Africa down to South Africa this is another narrow leafed species which has balloon like spiny follicles from which the genus derives name.
Grown from seed IAS1311 this perennial species from Mediterranean North Africa can be happily grown outdoors, but in Northern Europe is probably best lifted and over wintered in the greenhouse.
From South Africa, G. physocarpus is very similar in appearance to G. fruticosa, however the flowers are slightly larger, whilst the number of flowers in the umbel are generally less.
Grown from IAS1375 seed collected by Philip Alp (PRA348S) at Leeu-Gamka, north of Prince Albert in the Western Cape Province of South Africa, and offered on the list as Orthanthera species. However once it had flowered in 2004 it became clear that this was in fact a Gomphocarpus species.
Hoodia Sweet ex Decaisne
The genus is named for a Mr. Hood who was a succulent plant grower in England circa 1830. Distribution is in Angola, Namibia, Botswana, Zimbabwe and South Africa. Basally branched, often woody, spiny stem succulents. Stems usually erect but rarely procumbent, from 0.3 to 2.2metres in length. Relatively easy in cultivation, they require a well drained compost and a minimum 10°C winter temperature. The smaller growing species will readily flower in cultivation, whilst the larger species such as Hoodia gordonii seem less inclined to flower.
This species from the winter rainfall areas of southern Namibia, and the Northern Province of South Africa grows to a metre tall in habitat - the plant pictured is 40cm in cultivation.
From Namibia and the Northern Cape Province one of the larger growing species which in habitat forms large multi-stemmed plants up to a metre in height. The flowers are also amongst the largest of the genus and can reach in excess of 10cm in diameter in mature plants.
Grown from seed in 1996, this species from the Klinghardt Mountains of south west Namibia, began flowering at 4years in cultivation. This plant has a definite procumbent growth form and flowers freely over long periods, two or three times a year. The tubercles are arranged on 19-23 ribs.
From southern Namibia and the Northern Province of South Africa this species of upright habit is much less free flowering than ssp delaetiana. The tubercules are arranged on 14-22 ribs.
From the Little and southern Great Karoo regions of the Western and Eastern Cape Provinces of South Africa this multi-branched species rarely exceeds half a metre in height. The flowers are glabrous and papillate.
In the subfamily Marsdenieae, the genus Hoya, named after Thomas Hoy, a gardener at Syon House in England in 1821, is one of the best known and wide spread Asclepiad families. The distribution range is from Asia; Pakistan, India, Bangladesh, Bhutan, Myanmar, Nepal, China to tropical South East Asia, Papua New Guinea, Australia, Japan and numerous Pacific Islands, with over 300 described species. From fibrous roots the plants are epiphytic, rarely rooting in the ground, with stems that are rarely shrubby, more usually pendant or creeping, climbing and left twining, with white latex. The stems bear leathery succulent leaves and pseudo-umbellate flowers. The potting mix should contain added humus as compared to a normal succulent mix, and the plants prefer a humid atmosphere and should be kept watered all year round. As well as the described species there are numerous cultivars in circulation.
From India, Nepal and southern Myanmar this popular free flowering species is best grown in a hanging pot to accommodate its spreading stems bearing umbels of 8 - 10 flowers.
With their terminal inflorescences the thin, soft, pendulous stems of this species from India, Nepal and China can reach 1.5 metres in length, and the plant is thus best accommodated in a hanging pot.
From the Malaccan Islands this species is technically a climber, but in cultivation it tends to form a loose bush to a metre high and wide. The loose umbels of flowers with swept back petals resemble a flight of shuttlecocks.
From India and Nepal there is also one known locality in Australia but it is thought that the latter is probably the result of human introduction. The hairy stems produce umbels of up to 8 flowers.