Hakea gibbosa is an erect shrub to about 3 metres tall, usually less than 1 metre wide, with a conifer-like growth habit.
New growth is soft and hairy – a useful identification feature.
It has a small natural distribution, solely in NSW, growing generally between Wollongong and Wyong, close to the coast.
It is found in dry sclerophyll woodland and forest as well as heathland and sclerophyllous shrublands, mostly on Hawkesbury Sandstone soils and overlying sandy deposits.
Despite its comparitively small natural geographic range, it has become a serious weed in South Africa, New Zealand and Norfolk Island.
Adult leaves are narrow, up to 80 mm long by 1.5 mm diametre, tubular (terete) and rather prickly, mid-green to grey-green in colour.
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, flowers are creamy-yellow and grow in small clusters at the base of leaves. The flowering period extends from June to September. 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 perianths are to about 6 mm long with carpels to 8 mm long.
The woody follicles are large, up to 4 cm long by 3 cm wide, crowned with two horns and with woody wart-projections. Collecting fruits from plants is a rather painful experience.
Warren Sheather: One author describes the species as: “a grotesque prickly shrub”. We would not go that far in describing the species. It is certainly not a plant to grow near paths but is an eye-catching specimen when grown in native shrubberies. The dense, prickly foliage also provides safe nesting site for small native birds.
Hugh Stacy: Plants like friable soil and full sun and cannot stand frost.
Dan Clarke: A plant known to be cultivated and sold at some nurseries. It provides good habitat for birds. It is very prickly so consider the planting location (e.g., away from frequent-pedestrian areas).
Consider that this plant may become a weed in bushland where it does not naturally belong. Best grown in a sunny position on a well-draining soil.
Propagate from seed.
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 likely regenerates from seed after fire as it does not have a lignotuber.
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).
gibbosa – Latin meaning “hunched-backed” or “bumpy” – referring to the appearance of the fruit.
Australian Native Plants Society Australia (ANPSA) – Hakea gibbosa profile page https://anpsa.org.au/plant_profiles/hakea-gibbosa
NSW Flora Online (PlantNET) – Hakea gibbosa profile page https://plantnet.rbgsyd.nsw.gov.au/cgi-bin/NSWfl.pl?page=nswfl&lvl=sp&name=Hakea~gibbosa
Wrigley, J.W. & Fagg, M.I. (2001). Australian Native Plants – Propagation, cultivation and use in landscaping. 4th edition. New Holland Publishers, Pty. Ltd. Australia.