Euphorbia Species
Euphorbia antisyphilitica (Candelilla, Wax plant). Full sun. Hardy to 25°F. Evergreen shrub to 3' tall, mostly leafless stems. Little water. Native to Chihuahuan desert, west Texas, Mexico.
Euphorbia cactiformis. Full sun to light shade. Hardy to 25°F. Evergreen shrub to 6' tall; 6' wide. Little water. Native to Africa
Euphorbia resinifera (Moroccan mound); USDA: 9-11. Full sun to light shade. Hardy to 22°F. Spiny shrub to 4' tall; 6' wide. Moderate water summer. Native to Morocco.
Pedilanthus macrocarpus (Lady slipper) USDA: 9-10. Full sun to light shade. Little to moderate water. Hardy to 25°F. Evergreen bush to 6' tall; 6' wide. Origin: Mexico (Sonora, Baja California).