A group of fast growing, dwarf evergreen flowering shrubs and herbaceous plants, ideal for a sunny bank or a rock garden.
Family: Cistaceae (rock rose)
Botanical Name: Helianthemum
Common Names: Rock rose, sun rose
Foliage: Small paired leaves. Evergreen.
Flowers: Small saucer-shaped flowers borne in short racemes.
Flowering Period: Free flowering from late spring into summer.
Soil: Well-drained moderately fertile soil (chalk, clay, sand or loam). Alkaline or neutral pH. Does well in poor and sandy soils.
Conditions: Full sun. South, east or west facing aspect, in an exposed or sheltered position.
Habit: Low growing.
Type: Evergreen, semi-evergreen perennial.
Hardiness: Hardy through most of the UK.
Plant pot grown specimens between autumn and spring.
Suitable for rock gardens, front of the border
or as a ground cover on a sunny slope.
These highly vigorous spreading plants need to be pruned back by about a third after flowering, to ensure a compact and tidy habit. This may also encourage further flowering later in the season.
Generally pest and disease free. Can be affected by powdery mildew in very hot weather.
Propagate by seed or semi-ripe heel cuttings in early summer. Once rooted, pinch out the growing tips to help the plants bush-out. Plant out in the spring.
H. nummularium is the common species from which a number of good garden varieties have been developed. Average height to 6in (15cm) and spread up to 2ft (60cm).
H. 'Afflick' has rich green foliage and orange yellow flowers.
H. 'Ben Fhada' has silvery-green foliage with primrose yellow flowers from May to July. Available at Thompson and Morgan.
H. 'Firedragon' has green foliage and brilliant flame coloured flowers.
H. 'Georgeham' is a small evergreen form, with pink flowers that have a yellow central boss.
H. 'Peachy Keen' is a new double peach flowered variety with good foliage cover. Height to 8in (20cm), spread to 12in (30cm). Available at Thompson and Morgan.
H. 'Wisely Pink' has grey foliage and soft pink flowers.
H. 'Wisely Primrose' has grey-green
foliage and bright yellow flowers.