Content area
Full Text
With cheerful bright yellow flowers, these hardy shrubs and perennials are dependable all-rounders, says Petra Broddle
With around 400 Hypericum species and numerous cultivars distributed almost worldwide, there is a plant for every site. These range from low-growing, perennial herbaceous plants, to deciduous, semievergreen or evergreen shrubs up to 2m high.
All Hypericum varieties are recognisable by their star-like or cup-like, pale to golden yellow flowers. These range in size from 0.5cm to 8cm, with numerous, conspicuous stamens. Either single or clusters of flowers occur at the ends of stems, above the foliage.
The simple, oval to lance-shaped leaves are sometimes whorled, 1 cm to 8cm in length and vary in colour from dark green to grey-green, sometimes turning yellow or reddening in the autumn. H. rorrestii Award of Garden Merit (AGM) has a strong autumnal colour.
Branches may be upright or arching to matforming. Stems are sometimes red, and new shoots may be tinged purple. The flowers may develop into attractive black or red berries, which are popular with birds. Decorative sprays of leaves and fruit are also popular with florists.
The larger-growing H. 'Rowallane' AGM and H. 'Hidcote' AGM are some of the most useful and popular cultivars available for use in informal shrub and mixed borders, with long-flowering (June to October) and conspicuous yellow flowers. The low-growing, vigorous rose of Sharon, H. calycinum, is widely used as ground cover in dry, shaded areas, as are H. androsaemum (tutsan) and H. x moserianum AGM, which are less invasive. The larger H. forrestii AGM and H. 'Hidcote' AGM make attractive informal hedges. And as the plant is a vigorous grower, maximum height and spread are reached within five years.
The smaller species, such as H. olympicum AGM, prefer full sun and well-drained sites. Some alpine and Mediterranean species may require protection from wet cold. The larger species grow in sun or semi-shade and in fertile, but not too dry, soil. Some will tolerate dry shade, which makes them useful as ground cover under trees, but sunny positions and richer soil promote flowering. Most of the AGM hypericumsare hardy throughout the British Isles.
Hypericum requires little...