Because so may people liked the picture I put on my Facebook wall, I thought I’d write a bit more about Strophanthus speciosus. This plant belongs to the Apocynaceae, the same family the Adenium obesum (see previous post) belongs to. Most of the species in this family come from Africa, mainly from the tropical part, but one or two come from India, the Philippines or China. The S. speciosus comes from South-Africa. The name Strophanthus means twisted cord flower. Strophanthuses can be either climbers or shrubs.
The plants in cultivation are mainly grown from seed which will germinate in a couple of weeks in a temperature of about 20°C, but only if the seed is fresh, which you can achieve by hand-pollination. S. gerardii produces a tuber when grown from seed which I had not expected, as there is very little information in the literature about caudex Strophantuses. As far as I know that is the only caudex species, S. speciosus certainly does not have one.
They do not seem to be fussy about the soil type, but are not quick growers. They can be grown in either warm or cool conditions and are sometimes grown as container plants for moving outdoors in the summer. I have not tried it, but I doubt they can take frost. They do, however, have to grow to a fairly large size before they will flower.

Strophanthus speciosus