The humble Hakea

For a lesser-known member of the Proteaceae family, there are certainly a large number of species of Hakea. More than 180 species (and subspecies), in fact, across Australia, in every state and territory. The Proteaceae family also includes Grevillea, Banksia, Petrophile, Isopogon, Adenanthos and Conospermum.

Aboriginal peoples know the beauty and uses of Hakea plants and flowers.

The strong wood of Hakea arborescens can be used to make spears and boomerangs, and water can be extracted from the roots of Hakea leucoptera when water is scarce.

Several species of Hakea are popular bush tucker plants because the flowers are laden with nectar. Noongar peoples in the south-west of Australia roasted the woody fruits of Hakea prostrata in hot ashes and ate the seeds.

Hakea victoria flowers. Photo - Dave Blumer

The genus Hakea is named after Baron Christian Ludwig von Hake (1745– 1818), a German patron of botany. The first collections of Hakea by the scientific community were made by Joseph Banks and Daniel Solander in 1770, with the genus Hakea formally described in 1797 by Schrader and Wendland.

Diverse Hakea

Hakeas are endemic to Australia and 128 species occur in Western Australia, from Hakea chordophylla in the Kimberley region in the north, to Hakea ruscifolia in the south-west.

It is an extremely diverse genus, from low spreading shrubs to small trees.

Hakeas have flowers that look very similar to Grevilleas but can be differentiated by their persistent woody fruits.

Fruits vary from large, round cricket- ball-sized, as seen in Hakea platysperma, to the small, pointed fruit of Hakea smilacifolia. Many fruits have a beak and/or horns, which can be helpful in identification.

Hakea platysperma fruit. Photo - Dave Blumer

While many Hakeas have thick pungent (sharp) foliage, the leaves vary considerably in form and size, from terete leaves seen in Hakea adnata to large broad amplexicaul (stem-clasping) leaves with undulating prickly toothed margins seen in Hakea amplexicaulis. Perhaps the most spectacular foliage is seen in Hakea victoria, which has very large, multi- coloured leaves with distinct venation and prickly undulating margins.

Another species, Hakea trifurcata, has two completely different leaf forms on the same plant. The first type is terete with a sharp tip, while the second type is wide, short and oblong shaped. The second type mimic the shape of the fruit, acting as a decoy to seed predators.

The bark of most Hakeas is smooth, however some of the northern species, such as in Hakea lorea, has thick corky bark, which provides insulation from heat, enabling this species to withstand fire, re- shooting from epicormic buds in the trunk.

Garden friendly

Planting some stunning native Hakea species in your garden provides habitat and foraging resources for a variety of species. Hakea flowers produce large quantities of nectar, providing a valuable source of food to nectar-feeding birds, such as honeyeaters, and insects.

Insects provide important pollinator services to smaller-flowered species, whereas some small mammals, such as the pygmy possum, are thought to pollinate some of the larger flowered species. Black cockatoos are also known to forage on woody Hakea fruits, targeting the seeds and the larvae of wood-boring insects, as seen in Hakea prostrata. Hakeas are an important food source for the endangered Carnaby’s cockatoo (Zanda latirostris) in particular.

Honey possum (Tarsipes rostratus) on Hakea victoria. Photo - Janine Guenther

Hakea’s spectacular flowers are predominately white, cream, yellow, pink or red. However, there are exceptions, with Hakea lehmanniana being a very unusual purply-blue colour.

While Hakea inflorescences (group of flowers) all arise from the buds in the axils of leaves, they appear in three main configurations—a spike (an elongated raceme) like in Hakea francisiana, a globular cluster like in Hakea petiolaris or in small clusters in the leaf axils like in Hakea erecta.

The individual flowers of Hakeas have a perianth—the non-reproductive part of the flower—where the calyx (sepals) and corolla (petals) have merged to form a curved tube which sometimes splits open as the flower develops, the style terminates in a pollen presenter, which is an important diagnostic feature.

Kings Park and the Western Australian Botanic Garden have a range of beautiful Hakeas within their living collections, with approximately 100 different species growing throughout the gardens and bushland.

Hakeas flower mostly in winter and spring, but since Hakea fruit is as intriguing as the flowers, any time of the year is a good time to visit the gardens.