Widely distributed, it is found as an understorey plant in open dry forest or heathland from Victoria to northern Queensland, generally on sandstone though sometimes also clay soils.

It has long narrow leaves with inflorescences which can vary considerably in coloration; while the spikes are gold or less commonly yellowish, the emergent styles may be a wide range of colours – from black, purple, red, orange or yellow.

Banksia spinulosa was named by James Edward Smith in England in 1793, after being collected by John White, most likely in 1792.

The hairpin banksia is pollinated by and provides food for a wide array of vertebrate and invertebrate animals in the autumn and winter months.

Its floral display and fine foliage have made it a popular garden plant with many horticultural selections available.

Leaf undersides have fine white hairs in the case of the varieties spinulosa and collina and pale brown in cunninghamii and neoanglica.

[3] The distinctive inflorescences or flower spikes occur over a short period through autumn and early winter.

A spike may contain hundreds or thousands of individual flowers, each of which consists of a tubular perianth made up of four united tepals, and one long wiry style.

The style ends are initially trapped inside the upper perianth parts, but break free at anthesis.

The first known specimens of B. spinulosa were collected near Sydney by John White, Surgeon General to the British colony of New South Wales, sometime between 1788 and 1793.

It is uncertain exactly when he first collected the species; it may have been before 1790, as there is speculation that a sketch in his 1790 Journal of a Voyage to New South Wales is of a B. spinulosa infructescence.

"[8] More recently, however, Alf Salkin has argued that "the cone illustrated by White is probably not as suggested from the B. spinulosa described by Smith but, may be from another member of the complex or from one of the forms of B. ericifolia.

[9] Smith gave it the specific epithet spinulosa, a Latin term meaning having minute spines, probably in reference to the leaf tips.

[11] When George Bentham published his 1870 arrangement in Flora Australiensis, he discarded Meissner's series, placing all the species with hooked styles together in a section that he named Oncostylis.

[14] In 2005, Austin Mast, Eric Jones and Shawn Havery published the results of their cladistic analyses of DNA sequence data for Banksia.

They inferred a phylogeny very greatly different from the accepted taxonomic arrangement, including finding Banksia to be paraphyletic with respect to Dryandra.

collina in northern Queensland have old spikes bare as opposed to them having persistent old flower parts in New South Wales and Victoria.

[31] A molecular study with specimens of each subspecies from the three mainland eastern states they occur would shed light on this matter.

[2] Banksia "Giant Candles" was a chance garden hybrid between B. ericifolia and B. spinulosa var. cunninghamii.

A 1998 study in Bungawalbin National Park in Northern New South Wales found that B. spinulosa var.

collina was visited predominantly by native bees rather than the introduced Apis mellifera (European honeybee).

A 1982 study in the New England National Park in northeastern New South Wales found that a large influx of Acanthorhynchus tenuirostris (eastern spinebill) coincided with the start of local B. spinulosa's flowering.

As a result, it does not appear on the list of threatened flora of Australia under the Environment Protection and Biodiversity Conservation Act 1999.

Banksia spinulosa is listed in Part 1 Group 1 of Schedule 13 of the National Parks and Wildlife Act 1974; this means that as a common and secure species it is exempted from any licensing or tagging requirements under the 2002–2005 management plan to minimise and regulate the use of protected and threatened plants in the cut-flower industry in New South Wales.

spinulosa was introduced into cultivation in the United Kingdom in 1788 by Joseph Banks who supplied seed to Kew, Cambridge Botanic Gardens and Woburn Abbey among others; var.

Known as chlorosis, it manifests as yellowing of new leaves with preservation of green veins, and occurs when the plant is grown in soils of higher pH.

This can also happen where soil contains quantities of cement, either as landfill or building foundations, and can be treated with iron chelate or sulfate.

As most cultivated forms of this species have a lignotuber, dormant buds exist below the bark that respond to pruning or fire, and hard-pruning is possible almost to ground level as a plant can readily sprout from old wood.

spinulosa are commonly seen in nurseries; given that the varieties can hybridise, attempting to find a local provenance form from a local community nursery, Bushcare or Australian Plants Society group is preferable environmentally if they are intended for planting in gardens near bushland where native populations occur.