General Description:
Grevillea is a large genus of over 360 species, mostly confined to Australia but a few occur in New Guinea, Indonesia and New Caledonia.
Grevillea wickhamii is a variable species comprising six recognised subspecies (subsp.aprica, subsp.cratista, subsp.hispidula, subsp.macrodonta, subsp.pallida, subsp.wickhamii) which differ in flowering times, flower colours and growth habits.
Plants vary in height from low, shrubby forms to spindly trees up to 6 metres high. Leaves are oval or egg-shaped, wider at the base with toothed margins and are up to 100 mm long and 50 mm wide. The small individual flowers appear in clusters, usually on short stems from the leaf axils. The most commonly seen flower colour is orange-red but pink and yellow forms are seen depending on the particular subspecies. Flowers appear mainly during winter to spring.
G. wickhamii is a very attractive species with conspicuous flowers and attractive foliage. Various forms have been in cultivation for many years, particularly in tropical and sub-tropical areas. It has been grown in temperate ares but cannot be considered reliable in those regions unless grafted. It prefers a sunny position in well drained soils and will tolerate light frosts. It will tolerate extended dry conditions once established. G. wickhamii subsp. apica is the most commonly cultivated form and is usually about 2.5 metres high and wide (occasionally larger).
Propagation may be carried out from seed and germination is improved if the seed is carefully “nicked” with a sharp knife to expose the embryo. Cuttings are also successful and the species has been successfully grafted using Grevillea robusta as rootstock.

Grevillea wickhamii subsp. apica
Photo: Cas Liber

Grevillea wickhamii (a yellow form)
Photo: Brian Walters