Streptcarpus cyanandrus

Photo by Peter Yaremko,
courtesy Betty Tapping

S. cyanandrus is a tiny plant, which has been incorporated into a number of hybrids in the hope of obtaining smaller plants. Unfortunately, most of these hybrids have inherited S. cyanandrus' notoriously difficult cultural requirements. It's not clear to me exactly what is necessary to grow this plant well, as I have never been successful. Fairly cool temperatures and well-drained soil are the normal requirements of streps, although it hasn't worked for me with S. cyanandrus.  Another photo of the species can be seen here, and another with more decorative flowers here.