Best grown in dry to medium, well-drained soils in full sun to part shade. Must have sharply-drained soils. Plants generally have good drought tolerance, but appreciate some moisture in dry summer periods. Plants are tolerant of some poor soils, including rocky-sandy ones. Wet soils in winter can be fatal. Plants are considered to be evergreen in warm winter areas. Plants prefer a Mediterranean-type climate and may show some stress in hot and humid summers. Plants are not reliably winter hardy in USDA Zone 5 where they should be sited in protected locations with a root mulch. Pinch stems back to 6" in mid spring immediately after flowering to encourage bushy growth.