Ariocarpus retusus (Seven stars). Sunset: 11,13; USDA: 9b-11. Hardy to 27° F. Full sun to light shade, needs protection in hottest desert gardens. Solitary spineless, slowly growing up to 10" in diameter. Little water summer, no water in winter. White flowers with pink stripe in center, 2" in diameter. Origin: Mexico.  CITI protected. Cannot ship out of USA.