Echeveria 'Black Prince' is a hybrid by Frank Reinelt of Capitola, California between Echeveria affinis and Echeveria shaviana and is one of the darkest coloured Echeveria.
In winter, the colouration is more to the green side, but then will darken to purple or black in full sun.
Size is ultimately about 20cm (8") across, and about 15cm (6") high, with longer arching sprays of blooms reported to be crimson or dark red in late fall or winter.
When happy and large enough, it will eventually form a few to many offsets.
Echeveria 'Black Prince' will grow well in many conditions as long as the light is bright, and soil well drained.
It will apparently survive frost of several degrees, so something to play with.
Propagates by leaf cuttings, and beheading. As it only reluctantly offsets this is not a reliable form of propagation.
Best uses are as individual potted specimens, in succulent wreaths, or mixed container plantings. Combine Echeveria 'Black Prince' with Pennisetum or blue fescue and trailing blue or dark red Sedum in a clay or hypertufa pot for an eye catching look