A shrub that grows to 4 metres tall by 4 metres wide. The cultivar is very similar to Grevillea banksii which is one of the original parents. It is thought this cultivar is a cross between G. banksii and G. ‘Sandra Gordon’.
It has deeply divided, grey-green leaves, to about 10 centimetres long by 7 centimetres in width with linear segments to 0.3 cm across. The undersides of leaves have silver hairs.
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 orange-pink and cream and very showy.
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. In this cultivar, the carpels are to 40 mm long, cream with yellow tips. The perianths are pink-orange which makes a stunning contrast.
A very attractive plant for a garden situation with well-drained soil and full sun.
It is reportedly a very fast growing and hardy shrub. It tolerates a range of soils and can cope without supplementary watering, although plants will flower much more heavily if watered. Can tolerate hard pruning. Plants that may be several metres tall can be cut back to about 1 m tall (or lower) to refresh the plant and provide new dense growth. Works well as a screening plant.
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. 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 mainly in winter and spring. Spot flowering at other times. It can flower very heavily, creating a spectacular show.
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.
Grevillea is a diverse genus of about 360 species of evergreen flowering plants native to rainforest and more open habitats in Australia, New Guinea, New Caledonia, Sulawesi and other Indonesian islands east of the Wallace Line. NSW currently has about 85 species although with a lot of subspecies and some informal taxa recognised.
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”.
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.
‘Kay Williams’ – origins of name unknown.
All Natives Nursery – Grevillea ‘Kay Williams’ sales page https://www.allnatives.com.au/shrubs/3-to-6m-high/grevillea-kay-williams
Windyridge Nursery – Grevillea ‘Kay Williams’ https://www.grevilleas.com.au/grev19.html
Guildford Garden Centre – Grevillea ‘Kay Williams’ sales page https://guildfordgardencentre.com.au/product/grevillea-kay-williams/