Grevillea robusta

Grevillea robusta, nicknamed the Silky Oak of Australia, reaches impressive dimensions in its country of origin. In gardens, its growth will be less, giving a medium-sized tree with a pyramidal habit. It is very ornamental with its more or less evergreen, deeply cut foliage with a silvery underside and blooms magnificently in spring. Long elongated clusters appear, composed of numerous geometrically arranged yellow-orange flowers. These inflorescences further enhance the tropical appearance of this fast-growing tree. A superb, tender plant, perfect for creating a typical exotic scene.

Grevillea robusta is a tree from the Proteaceae family, which includes 83 genera with some of the most beautiful flowerings in the world (Banksia, Telopea, Protea...). The robusta species is the largest in the Grevillea genus. In Australia, it grows in Queensland and New South Wales, in a subtropical and temperate climate, from coastal areas up to an altitude of about 1100 m (3608 ft 11 in). In the rainforests of these regions, it commonly exceeds 30 m (98 ft 5 in) in height. From the mid-19th century, it began to be planted in many countries with a favourable climate, in other continents: America, Asia, Africa... and in France on the French Riviera, which offers it both the sunshine it needs and sufficiently mild winters.
On the Mediterranean coast, on the southeast side, it forms a medium-sized tree with a distinctly pyramidal habit in the early years. Then, it can expand in a more or less irregular manner, while its height exceeds 10 m, and can even reach up to 15 m (49 ft 2 in) with a width of 6 or 7 m (19 ft 8 in or 23 ft). Its generally straight trunk has a dark, highly veined bark. It supports dense vegetation, highly branched in all directions, forming a dark green mass of foliage. The leaves are extremely architectural. Their leaf is deeply cut, notched up to the central vein, as if they were composed of leaflets themselves again cut. Measuring 15 to 30 cm (5.9 to 11.8 in) long, olive green to dark green in colour, their undersides are silver-grey. Evergreen if the frost is not pronounced, they are decorative all year round, giving this tree an unmatched grace.
From May onwards, long flower clusters measuring up to 15 cm (5.9 in) long appear. These racemes are composed of small flowers, of which the delicately arched, protuberant, yellow-orange stigmas are particularly admired. Their geometric arrangement gives the impression of a hairbrush, confirming this tree belongs to the Proteaceae family, whose flowerings are often graphic masterpieces. This singular, abundant and nectar-rich flowering extends over several weeks, further enhancing the exotic aspect of this Grevillea. Unlike other Proteaceae, highly demanding in terms of soil, this one is relatively accommodating in terms of soil. Hardy down to about -6°C (21.2 °F), or even down to -8°C (17.6 °F) at its coldest for a mature specimen, it does not appreciate cold winds and should therefore be planted in a protected position, exposed to the sun.

Grevillea robusta, with its quick growth, will be the centrepiece of an exotic bed in very sunny coastal gardens. Other Austral plants such as Callistemons, these famous bottlebrushes whose flowers resemble bottle brushes, can be planted alongside it. Whether they are red, pink, white or violet depending on the species, their spectacular inflorescences will rival the beauty of those of the Grevillea. Another Australian shrub, Leptospermum scoparium Martini with its multitude of single pink flowers, will have a place in this bed. You can also try other Proteas such as Leucospermum Copper Carnival, a superb variety with large yellow flowers from this mythical genus, prized by collectors but difficult to cultivate...