Grevillea robusta, commonly known as Silky Oak, is an iconic Australian native tree valued for its fast growth, graceful fern-like foliage, and spectacular display of golden-yellow flowers. Flowering from late spring through summer, this impressive tree provides seasonal colour while creating valuable habitat and a rich source of nectar for birds, bees, and other pollinators.
Naturally occurring in the subtropical rainforests of eastern Australia, Silky Oak thrives in well-drained soils and performs best in a full sun position. Its attractive, finely divided foliage creates light, dappled shade, making it an excellent feature tree for large gardens, parks, rural properties, and avenue plantings. In its natural habitat it can reach up to 30 metres in height, although it typically grows 10–15 metres in cultivation.
Once established, Silky Oak is relatively drought tolerant, fast growing, and widely recognised for producing quality timber used in furniture and cabinet making. As a large tree, it requires adequate space to develop its broad canopy and should be planted well away from buildings and overhead services. It naturally drops seed pods and seasonal leaf litter, making it better suited to larger landscapes than smaller suburban gardens.
In some regions outside its natural range, Grevillea robusta has become an environmental weed due to its ability to self-seed readily. It is best avoided near bushland or environmentally sensitive areas where natural regeneration could occur.
How To grow the Silky Oak – Basic Care
Originally from New south Wales and Queensland Grevillea robusta or ‘Silky Oak’, is now grown widely across Australia and grows well as far south as Melbourne and Tasmania.
One established Grevillea robusta is a hardy drought tolerant tree that requires little care. A well drained soil is essential as it doe not cope well with being water logged.
The root system is vigorous and this is a tree that is best planted 15 – 20 metres away from drainage lines and sewerage systems. Plants are easily propagated from seeds, seedling trees will need to be protected from grazing animals using trees guards.
Summary
- Botanical Name – Grevillea robusta.
- Common Name – Silky Oak.
- Position – Full Sun.
- Soil – Well drained.
- Height – In cultivation 8m, however can reach to 30m depending on conditions
- Spread – Crown will spread to 14 m on a mature tree in an open position.
- Flowers – Golden Yellow
- Flowering Time – Spring.
- Foliage – Mid to deep green.
- Root system – Vigorous and shallow.
- Growth Rate – Regarded as fast.
- Attracts nectar seeking birds as well as possums.
- Range – Grows well from Queensland, through New South Wales to Victoria.