Grevillea robusta (Silky Oak)
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.
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
Requirements
| Hardiness | 10 – 12 |
|---|---|
| Heat Zones | 3 – 12 |
| Climate Zones | 8, 9, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, H1, H2 |
| Plant Type | Trees |
| Plant Family | Grevillea |
| Exposure | Full Sun |
| Season of Interest | Spring (Early,Mid,Late)Summer (Early,Mid,Late) |
| Height | 70' (21m) |
| Water Needs | Low |
| Maintenance | Low |
| Soil Type | Loam, Sand |
| Soil pH | Acid, Neutral |
| Soil Drainage | Moist but Well-Drained, Well-Drained |
| Characteristics | Plant of Merit, Showy, Evergreen |
| Native Plants | Australia |
| Tolerance | Deer, Drought |
| Attracts | Birds, Butterflies, Hummingbirds |
| Garden Styles | Mediterranean Garden |