Description
Hibiscus – Giant Mallow – Mallow – Rose Mallow –
There are about 220 species of deciduous and evergreen shrubs, trees, annuals and herbaceous perennials, in this genus. They are widely distributed in warm temperate, subtropical and tropical regions, where they occur in a variety of habitats, including stream side, moist woodland, and dry, rocky sites. They have alternate, smooth edged or shallowly to palmately lobed, sometimes toothed leaves, and are grown for their showy, 5 petaled, mainly funnel shaped, held solitary or in clusters, borne over a long period from spring to autumn. The flowers are red, pink, purple, blue, yellow or white and sometimes have contrasting marks at the bases of the petals, and prominent, colorful stamens. Grow in a sunny mixed, herbaceous, or shrub border. Some perennials may be grown as annuals or hedges.
Outdoors, grows in humus rich, moist but well drained, neutral to slightly alkaline soil in full sun. Hibiscus need long, hot summers to flower well. Trim after flowering to maintain shape. Most are drought and frost tender.
Prone to rust, fungal leaf spots, bacterial blight, Verticillium wilt, viruses, stem rots, root rots, whiteflies, aphids, mealybugs, scale insects, mites, Japanese beetles, and caterpillars.
H. arnottianus – Hawaiian White Hibiscus – This fast growing, rounded, usually fairly open, evergreen, large shrub or small tree from Hawaii grows 10-25′ feet tall and 6-20′ feet wide. From arching branches it carries oval, smooth edged or toothed, leathery, mid green leaves, to 10″ long. In summer it bears 5 petalled, solitary, lightly scented, funnel shaped white flowers, 4-7″ across, with pink veins and central sheaves of red stamens, and may last only up to 2 days.
Zones 14-15