Fast-growing and stately, Grevillea robusta (Silky Oak) is an evergreen tree of great beauty. Pyramidal when young, it develops a few horizontal limbs when older, giving it a broader top. Mature specimens produce a striking display of large, rich, bright golden orange flowers, up to 5 in. long (12 cm), in dense, one-sided spikes in spring-summer. Equally attractive is the foliage of olive-green, fern-like leaves, to 12 in. in length (30 cm), silvery underneath. Frost hardy to 16°F (-8°C), although it becomes semi-deciduous under those conditions, Silky Oak is often grown as an annual for the beauty of its foliage.
- Recipient of the prestigious Award of Garden Merit of the Royal Horticultural Society
- Grows up to 75 ft. tall (22 m).
- Easily grown in acidic, well-drained soils in full sun. Drought tolerant once established. Use little to no phosphorus fertilizer.
- Deer resistant
- Great as a specimen plant in Mediterranean gardens and xeriscape gardens.
- Virtually disease free and pest free.
- Propagate by seed, semi-hardwood cuttings or graft.
- Native to Australia