Adenium obesum, Desert Rose. Admittedly, not a landscape plant in our climate, but wow! look at this specimen from the Chiangmai flower show in northern Thailand! It's almost 4 ft. across and is trained as a bonsai. These can be grown in containers here, just make sure to keep them warm, sunny and dry in the winter (indoors) and don't over-water in the summer. They are native to sub-sahara desert areas of Africa and are in the Oleander family, so all parts are poisonous, even their beautiful flowers.