They are moderately to very frost hardy, they are easily grown in moist, well-drained soil and need a position in sun or light shade. After flowering, cut some older shoots back to young growths, leaving young shoots to flower the following year.
You can propagate by seed, by softwood or greenwood cuttings in the summer, or by hardwood cuttings in the autumn to winter.
Pests, diseases or disorders
May become infested with aphids.