Grevillea crithmifolia is a shrub that comes in two forms. One is a compact 2-metre tall shrub. The other is a dense ground cover with a height of around 0.5 metres and a width of at least 2 metres.
It is another endemic species to Western Australia, growing very close to the west coast, between Bunbury in the south and Cervantes in the north.
Leaves are alternate up the stem, to 30 mm long, divided (pinnatisect) to be tri-partite with segments about 1 mm wide, overall leaves about 20 mm across; light green in colour.
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 produce the inflorescences mostly at the terminals, beyond the foliage, which differs to the closely related Hakea.
This species is a more-or-less a spider-flower, with flowers occurring in dense clusters of white or pink flowers in umbel-like heads at the terminals. Each head is about 2.5 cm across, mainly occurring in spring.
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 species, the perianth is about 5 mm long, white to pink with the carpels to about 10 mm long, also white to pink.
The fruit is a follicle to about 15 mm long.
This species is known to be cultivated successfully. It is a hardy shrub and flowers well in most situations.
The groundcover form is the one most favoured by gardeners. A well-grown, ground covering form of Grevillea crithmifolia will form a dense, weed-suppressing carpet.
The other form can become a nice shrub, to 3 x 3 metres in some cases.
Best grown in an open and sunny position on a well-drained soil.
The Editor will not go into too much detail here but flowers are reported to have an interesting and recognisable smell which offends some people.
Prune lightly after flowering to maintain dense foliage.
Propagate from cuttings which may be slow to produce roots.
This species likely regenerates from seed aftre fire.
Grevillea is a diverse genus of about 365 species with about 357 occurring in Australia. Some species occur in New Caledonia, Indonesia and New Guinea. NSW currently has about 85 species although with a lot of subspecies and some informal taxa recognised.
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.
crithmifolia – Latin – having leaves similar to Crithmum – a genus of samphires in the Apiaceae family which grow on rocks along the coast in Europe.
This species is not considered to be at risk of extinction in the wild.
Western Australian Herbarium (1998–). Florabase—the Western Australian Flora – Grevillea crithmifolia profile page https://florabase.dbca.wa.gov.au/browse/profile/1982
Gardening with Angus – Grevillea crithmifolia profile page https://www.gardeningwithangus.com.au/grevillea-crithmifolia-grevillea/
Wrigley, J.W. & Fagg, M.I. (2001). Australian Native Plants – Propagation, cultivation and use in landscaping. 4th edition. New Holland Publishers, Pty. Ltd. Australia.