Growing Hypericum (St. John’s Wort)
Common name: St John’s wort
Members of thegenus are easy-to-grow, undemanding shrubs that can be relied upon to brighten up dull spots in the garden. The best known and most widely available is the rose of Sharon ( ), which will thrive in numerous difficult positions — under trees or on dry banks, it does not seem to matter. It is a vigorous grower, and ideal for providing ground cover. But it can become a nuisance.
Popular species and varieties
Hypericum calycinum produces large golden with conspicuous stamens, from late spring to early autumn, over dense growth of 45cm (18in) in height There are a considerable number of alternative species, including H. kouytchense (AGM). This has upright growth and deep yellow flowers with very long stamens, carried in early and mid-summer. They are followed by red seed capsules.
Onethat is very popular is ‘Hidcote’ (AGM), producing a long succession of rich golden blooms on neat, 1.2m (4ft) high bushes, from late spring until late summer.
Soil type Any non-garden .
Planting This can be carried out in the autumn or spring, in open, sunny or lightly shaded areas.
Pruning In late winter, every few years, Hypericum calycinum should be cut back hard. This will keep it compact. At other times trim to keep it in shape.
Propagation Semi-ripe cuttings with a heel, taken from non-flowering shoots in the summer.
Pests and diseases Generally trouble free, although Hypericum calycinum can be attacked by rust.