Asclepiadaceae

The Lyon Botanical Garden has a 275 taxons and 42 genera rich collection. Hardy and half hardy Asclepiadaceae are cultivated in the botany school and the succulent ones are in the cactus greenhouses (cold little greenhouses).

Huernia laevis
J.R.I. Wood

Status and conservation

38 taxons of our collection have a protection status (IUCN status).

3 of them are vulnerable : Caralluma hexagona, Caralluma burchardii, Huernia hystrix
6 taxons are endangered : Ceropegia armandii, Ceropegia petignatii, Duvaliandra dioscoridis and Frerea indica.
28 taxons are rare : Ceropegia dichotoma, Ceropegia dimorpha, Ceropegia fusca, Ceropegia hians, Ceropegia radicans, Cynanchum compactum, Cynanchum macrolubum, Cynanchum marnerianum, Hoya macgillivrayi, Stapelia tsomoensis, Stapelianthus decaryi, Stapelianthus hardyi, Stapelianthus insignis, Stapelianthus keraudreniae, Stapelianthus madagascariensis, Stapelianthus montagnacii, Stapelianthus pilosus and Vincetoxicum rossicum

The collection in the botany school :

The plants are placed following their botanical family. You can see 10 specimens of the Asclepiadaceae family there. We cultivated semi hardy plants such as Gomphocarpus fruticosus, a shrub with strange bulging and thorny fruits, and the beautiful Asclepias curassavica with its remarkable sharp orange flowers and its prolonged flowering from June to October. We replace these two frost-cleft plants each year. The other plants you can see are perfectly hardy such as Cionura erecta and the vigorous liana Periploca graeca, both coming from Balkans.

Concerning plants coming from Europe we also cultivate Vincetoxicum hirundinaria, which is common in our countries, Vincetoxicum nigrum and Vincetoxicum rossicum, they both look like Vincetoxicum hirundinaria but they have very beautiful dark crimson flowers.

Stapelianthus decaryi
Choux

The collection in the succulent plants greenhouses is divided in four geographical sectors :

Madagascar zone :
We cultivate there Stapelianthus hardyi, Stapelianthus keraudreniae, Stapelianthus insignis or Ceropegia dimorpha.
The genus Spatelianthus (circa 10 taxons) is endemic in Madagascar. This genus is demanding for heat and that grows – in its natural environment – under shrubs on a dry ground

East Africa zone :

In this part you can see the amazing Edithcolea grandis with its imposing big flowers and Caralluma somalica with its strange bilberry perfume. We also show there : Carralluma arachnoidea, Echidnopsis planiflora, Echidnopsis cereiformis, Echidnopsis nubica, Huernia macrocarpa var. penzigii,…

Stapelia hirsuta
L.

South Africa zone :
It contains a rich collection with about 10 genera coming from this country. We cultivate Orbea variegata, which is the first Asclepiadaceae that was described, its author placed it into the family of the tulips, Hoodia bainii and Hoodia goordonii with their large round flowers that evoke a mushroom, or Stapelia hirsuta with its hairy dark red flowers that evoke the flesh of a dead animal and produce the smell of a dead body., Ceropegia stapeliformis, Duvalia reclinata, Fockea edulis, Huernia histrix var. parvula, Huernia pendula, Raphionacme hirsuta, Stultitia hardyi,…

North Africa, Canaries and India zone :
You can see there Caralluma europea var. marocana, which is the only european representative of the Stapeliae group with the variety confusa. Frerea indica is a strange plant because it is the unique member of this group to have true leaves, it is a testimony of the link between the succulent Asclepiadaceae and the rest of this family. We also cultivate : Caralluma burchardii var. maura, Caralluma comutata, Ceropegia fusca, Ceropegie dichotoma…

The genus Ceropegia has an important geographical distribution that covers Asia, Australia and Africa and its flowers constitute true traps for the insects.

Ceropegia rupicola
Deflers

Arabia, Yemen and Socotra zone :

The imposing one meter high Caralluma penicillata dominates this zone, under this plant you can see endemic and protected plants from Socotra island : Duvaliandra dioscorodis, Caralluma socotrana…

You can also find there : Caralluma lavrani, Caralluma hexagona, Caralluma plicatiloba, Ceropegia rupicola, Echidnopsis squamulata, Huernia transmutata…

Cultivating succulent Asclepiadaceae

The main character of the cactus greenhouses is their high luminosity during the winter. At this period we keep a 12°C minimal temperature with low watering. We use a draining and acid mix composed of loam, sand and heat-mould as a subtratum. Some plants are too fragile so we have to graft them. It is a delicate operation that demands experience because we have to solder the roots of rot-resistant plants (such as Stapelia nobilis or Ceropegia woodii) with the aerial part of the plants that we have difficulties to cultivate (such as Hoodia sp. or Stapelianthus pilosus). We make the grafting between May and September, when the plants are full of sap. For the least fragile ones, we easily shoot them.

Asclepias tuberosa
L.

Generalities

The conditions of pollination of Asclepiadaceae by insects reach a rare perfection degree that we can compare with another family : the Orchidaceae. As examples we can quote the pollen that is gathered in pollinia (a very particular character that the Asclepiadaceae share with the Orchidaceae), the frequent presence of an additional corolla, some flowers are malodorous and sometimes with vibrating hairs – that make them look like as if they were alive with insects – frequently evoke rotting meat.

Other characters of this family are a latex producing system that one can easily observe when the plant is cut and a very particular fruit that looks like a pair of horns. The Asclepiadaceae are mainly tropical and subtropical but some species grow under temperate climates (Vincetoxicum hirundinaria is the only Asclepiadaceae in our regions).

The family is composed of herbaceous plants, shrubs, climbing plants, trees, but also succulent plants (Stapeliae group) and epiphytic plants (Hoya linearis, Dischidia rafflesiana…).

Several genera are cultivated as ornamental plants, as an example Hoya carnosa, Stephanotis floribunda, Gomphocarpus futicosus under a favouring climate and Asclepias syriaca, Asclepias incarnata or Asclepias tuberosa under a temperate climate.

Contrary to the Apocynaceae (a family that is close to the Asclepiadaceae, some modern botanists gather the two families into the Asclepiadaceae), they aren’t very used as medicines. In Africa, people use some succulent species as a thirst or appetite suppressant (Hoodia sp., Quaqua mamilaris), or as a water stock (tubers from Fockea sp. or Raphionacme burkei).

We can notice the partnership with ants of an epiphytic Asclepiadaceae : Dischidia sp. that have folded up leaves sheltering colonies of this amazingly sociable insect.

Last modified: 06/07/2006 05:56 PM