Best grown in lean, dry to medium, well-drained sandy loams in full sun. Plant stems tend to flop, particularly in hot, humid climates such and/or if grown in moist, rich soils. Consider cutting back plant stems in late spring before flowering to reduce overall plant height. Cutting plants back to lateral flower buds after initial flowering will tidy the planting and encourage additional bloom. Plants may also be cut back to basal foliage after bloom.