A shrub to 2 metres tall, spreading to 1 metre wide, not possessing a lignotuber.
It has a naturally restricted occurrence, growing in the upper Blue Mountains west of Sydney, in the Mount Victoria, Leura / Katoomba (and south) and Newnes areas, as well as Clarence near Lithgow. It grows in swampy habitats of wet heath or mallee-heath, mainly on sandy soils / sandstone.
The leaves are rigid and needle like / tubular (terete) to 6 cm long and only 0.2 cm wide. They may have hairs but not many and end in a sharp point, and densely clustered on the stems.
A hakea inflorescence is technically a cluster of paired flowers, termed a conflorescence (although sometimes the paired flowers are not evident) with the overall structure forming a clustered-raceme-like appearance. The inflorescences are always produced in the leaf axils, as opposed to the closely related Grevillea where they are mostly terminal. They can appear as a spider-flower-like cluster, or a rounded ball where flowers emerge around a 360° radius, or as a cylindrical raceme (which strongly resemble those of Grevillea).
In this species, the inflorescences occur as loose clusters in the leaf axils, with up to 7 flowers per cluster, to 20 mm long and 30 mm wide, deep creamy-yellow in colour, primarily from August to October.
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, flowers are only about 1 cm long in total, mostly yellow in colour.
The woody follicle is oval in shape with small wart-like protuberances, to 4 cm long and 3 cm wide with a short broad beak and sometimes horned.
In the garden it grows in sun or shade in most soils with reasonable drainage. A hardy plant that can be pruned to shape. It has a history of having been successfully grown by APS members. It can be kept as a low dense bush, providing excellent habitat value in gardens. The yellow flowers also make this plant different from most others of the genera. Useful for bird shrubberies.
Hakeas are popular ornamental plants in gardens in Australia, and in many locations are as common as grevilleas and banksias. Several hybrids and cultivars have been developed, including ‘Burrendong Beauty’. They are best grown in beds of light soil, which are watered but still well-drained.
From seed which is available commercially.
This species was formerly thought to be a Blue Mountains form of Hakea propinqua.
Hakea is a genus of about 150 species of plants that are endemic to Australia, first described in 1788 by Joseph Gaertner, a German botanist. NSW currently has about 31 species, some which are species-complex.
Hakeas are similar to species of Grevillea but are distinguished from them in having persistent, woody fruits. Those of grevilleas are not persistent and not woody.
The fruit of Hakea spp. generally persist on plants until burned in a bushfire or until the plant dies. The fruit then splits open to release two winged seeds. This species does not have a lignotuber and so likely regenerates from the seed bank after fire.
Hakea – named after Baron Christian Ludwig von Hake (Baron von Hake of Hanover, 1745-1818), an 18th-century German patron of botany (and for whom not a lot of information can be found).
pachyphylla – from Greek pachys (παχύς) meaning ‘thick’ and phyllon (φύλλον) meaning ‘leaf’, referring to the thick leaves of this species.
This species is not considered at risk in the wild but has a limited distribution.
NSW Flora Online (PlantNET) – Hakea pachyphylla profile page https://plantnet.rbgsyd.nsw.gov.au/cgi-bin/NSWfl.pl?page=nswfl&lvl=sp&name=Hakea~pachyphylla
Australian Native Plants Society Australia – Hakea Study Group Newsletter No. 66 https://anpsa.org.au/wp-content/uploads/hakea66.pdf
Wikipedia – Hakea pachyphylla profile page https://en.wikipedia.org/wiki/Hakea_pachyphylla