Cultivation
There are many species but they all share the same general cultivation needs. They are fully hardy to frost tender, min 4-7C and will prefer dappled shade, but a considerable number will tolerate full sun, especially in cool climates. They will need loose open, well-aerated, acidic soil with plenty of humus to retain moisture. In wet areas or gardens with alkaline soil you should plant them in raised beds. Shallow planting is essential, as plants are surface-rooting. Dead-head spent flowers, wherever practical, to encourage energy into growth rather than seed production.
Propagation
Propagate by simple layering, dropping or semi-ripe cuttings in late summer.
Pests, diseases or disorders
Yellowing leaves are usually caused by poor drainage, excessively deep planting or lime in soil. Weevils and powdery mildew may also cause problems.
