10cm, a very rare subspecies growing at subalpine level of vertical cliffs of the highest peaks in central Madeira. Differs in the above by having a broader leaf basis and slightly more succulent, glossy, dark green leaves, shaded purplish red in a sunny spot topped with lax inflorescence of pure white flowers. For any rocky soil in a sunny spot. Keep sunny and drier in winter at a minimum of some 5°C. Will endure slight frost in autumn. For the cold frame or alpine house. USDA Climate Zone 9. VI-VIII.