The starfish-like Orbea dummeri

Hailing from East Africa, Orbea dummeri is one of the most well-known of the stapeliads, with flowers that look more like sea creatures with bear-trap maws and tentacled arms than anything else. Their ease of growth and free-flowering habit also contributes substantially to their popularity worldwide. These plants bloom during spring to summer, sometimes extending up to early autumn.

Note the inward-pointing trichomes around the corona. These may serve to facilitate the entry of potential pollinators to the vicinity of the corona, but dissuade them from leaving too soon, forcing them to linger on the corona and therefore increasing the likelihood of them picking up a pollinia or effecting pollination.


Because it's from equatorial climates, O. dummeri is very easy to maintain in the tropics. The plants can withstand very harsh conditions, from full sun and prolonged periods of drought, to heavy rains. The plants are better off sheltered during tropical typhoons, however.

The flowers are 4 cm across and have a very faint, sourish odor. I have observed ants visiting the blooms, but for obvious reasons, not the usual bluebottle flies one associates with stapeliads; this is one reason why I do not subscribe to calling these plants 'stinkies' precisely because it is a generalization that is far from being applicable to the group as a whole. Like many stapeliad flowers, the corolla is beset with trichomes, but those on this species are quite different. The surface is ornamented with papillae terminating in translucent hair-like trichomes with clavate tips, which are more developed on the corolla margins. Compared to stapeliads beset with trichomes, those on O. dummeri are stiff and do not sway in the breeze. Another unusual trait is that the buds often pop open in the afternoons, instead of in the morning like most flowers do, including stapeliads.

An ant navigating through the intricate corona.

This bud started opening in the morning, but waited until afternoon to fully display the flower itself.

My plant is being cultivated in a purely mineral mix, with some pellets of balanced time release fertilizers replenished every three months. During the dry season it gets watered about once every seven to ten days. Due to it being kept unprotected from the sun, the stems have developed dark reddish striations and irregular maculations, a result of elevated production of anthocyanin pigments.

The heavily mineralized mix of my O. dummeri.

Orbea dummeri has ethnobotanical importance. Find out more here: http://www.llifle.com/Encyclopedia/SUCCULENTS/Family/Asclepiadaceae/30564/Orbea_dummeri

Fortunately, this species is fairly easy to obtain and is a good plant for novices to the world of succulents, especially stapeliads. They grow quite rapidly and tolerant of various conditions, and the flowers appear quite gregariously, which gives a quite spectacular look especially when the plants have achieved enough stem density. But as with most succulents, a mainly mineralized mix is highly recommended to avoid potential problems, including insect attacks and rot.

Orbea dummeri flowers may either be green or yellow.

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