Grevillea ‘Sunset Splendour’ (‘Sunset Bronze’)

(cultivar)

Family: Proteaceae

A shrub that grows to 3 metres tall by 3 metres wide. This cultivar reportedly originated in a garden in Brisbane and is thought to be a chance hybrid between Grevillea ‘Honey Gem’ and a northern form of G. pteridifolia.

It has dark green-grey, attractive, deeply divided leaves (pinnatisect) to 20 centimetres long by 15 centimetres wide, with resulting opposite linear segments about 0.5 cm wide. The foliage takes on a bronze sheen in winter, especially the new growth.

A grevillea inflorescence is technically a cluster of paired flowers, termed a conflorescence with the overall structure forming a raceme-like appearance. Grevillea species exhibit 3 main inflorescence structures:
– 1. A cylindrical to ovoid raceme (with flowers emerging around a 360° radius)
– 2. A single-sided raceme (with flowers produced on only one side, resembling a tooth-brush)
– 3. A condensed or clustered raceme (usually as long as it is wide, with species referred to as the spider-flowers)

Grevillea mostly produce the inflorescences at the terminals, beyond the foliage, which differs to the closely related Hakea.

This cultivar has a cylindrical raceme, with inflorescences to about 15 centimetres long by 8 centimetres wide. They are a burnt-copper colour (deep orange-brown) with yellow, produced in spring to summer.

Individual flowers are composed of 1 carpel (female part) where the style and stigma protrude out; 4 stamens hidden away in the perianth; and the perianth (petals and sepals collectively) which connects to a pedicel. Proteaceae flowers do not have any discernible petals or sepals (having only one whorl) and so these are referred to as “tepals” of which there are 4.

The carpels are to 40 mm long, orange with yellow tips. The perianths are burnt-orange/copper.

In the garden

A very attractive plant for a garden situation. The contrast of the burnt-orange/copper inflorescences green-grey foliage is quite stunning. It is reportedly a very fast growing and hardy shrub. It has sub-tropical origins and so does better with additional watering does not tolerate heavy frost. It tolerates a range of soils, so long as drainage is adequate. Can tolerate hard pruning where plants that may be several metres tall can be cut back to about 1 metre tall to refresh the plant and provide new dense growth. Flowering is much improved with pruning.

Very good cut flower, harvest when the inflorescence is in bud rather than full-flowered. The inflorescences are of a good large size and are produced over much of the year. Excellent bird and insect attractor.

Propagation

Grevilleas are propagated by three principal methods; seed, cuttings and grafting. To maintain desirable characteristics of a particular plant, vegetative propagation (e.g. cuttings or grafting) must be used. This also applies to propagation of named cultivars.

Other information

Grevillea flowers were a traditional favourite among First nations Peoples for their sweet nectar. This could be shaken onto the hand to enjoy, or into a coolamon with a little water to make a sweet drink. They might be referred to as the original “bush lollies”.

Note: The correct registered cultivar name is ‘Sunset Splendour’. However, it also goes by and, is marketed, as ‘Sunset Bronze’.
Although not yet recorded, the cultivar is very similar to several cultivars which have been known to cause allergic contact dermatitis for certain individuals who come into contact with it, so caution is advised.

Grevillea – was named in honour of Charles Francis Greville (1749-1809), an 18th-century patron of botany and co-founder of the Royal Horticultural Society. He was also a British antiquarian, collector and politician who sat in the House of Commons from 1774 to 1790.

‘Sunset Splendour’ – likely named for the colour of the inflorescences.

https://www.grevilleas.com.au/grev61.html

https://www.burkesbackyard.com.au/fact-sheets/in-the-garden/flowering-plants-shrubs/grevillea-sunset-bronze/

https://www.gardeningwithangus.com.au/grevillea-sunset-bronze-grevillea/

By Dan Clarke