I wrote recently about watering during an extended hot spell, and while working today I was…
They will thrive in fertile, well-drained soil with full sun. You can propagate by division in the spring or from seed in the spring or autumn.
You can propagate by seed in autumn or spring or by softwood or semi-ripe cuttings of non-flowering shoots in mid-summer. Propagate cultivars by cuttings.
Pests, diseases or disorders
May be damaged by slugs and snails and powdery mildew.