Dichroa febrifugaThis unusual shrub is sometimes known as the 'evergreen Hydrangea', and it belongs to the same broad family as the more familiar Hydrangea. It is a native of the foothills of the Himalayas from Nepal to China and Vietnam. It grows to around 2-3 m tall, with large evergreen toothed leaves. The flowers are star-shaped with prominent blue stamens and are massed in large rounded clusters. It is said that the flower colour will reflect the pH of the soil, so more acid soil will produce richer blue blooms and more alkaline soil will lead to pink-tinged ones. Bright metallic-blue berries can occur after flowering. It is regarded as a medicinal plant in China.
Lacecap Hydrangea macrophylla (left) with Dichroa febrifugaDichroa is in bloom for a longer time than Hydrangea, with flushes from October to April. Deadheading of spent flowers, to a point where a new pair of shoots is forming, will encourage this. It will grow in sun or part shade: apparently the colour of the flowers is more intense in shade, but the shape of the plant may become more open. It is also said to tolerate boggy or dry soil! It is tolerant of frost in colder Sydney suburbs. I have found it strikes very readily from cuttings and seems ideally suited to the Sydney climate. Dichroa looks good grown with true Hydrangea shrubs, to add interest; its tiny flowers echo the central fertile florets of the beautiful lacecap Hydrangea cultivars, as shown in the photo above.
There are other similar species; I am not sure which, or in fact which one I actually have! Another species, Dichroa versicolor, has been said to be distinguishable from Dichroa febrifuga by the near-black colour on the new growth of its stems. It seems that botanists now call Dichroa febrifuga by the name of Hydrangea febrifuga but that name has yet to catch on amongst gardeners!