About

Banksia aemula, commonly known as the wallum banksia, is a shrub of the family Proteaceae. Found from Bundaberg south to Sydney on the Australian east coast, it is encountered as a shrub or a tree to 8 m (26 ft) in coastal heath on deep sandy soil, known as Wallum. It has wrinkled orange bark and shiny green serrated leaves, with green-yellow flower spikes, known as inflorescences, appearing in autumn. The flower spikes turn grey as they age and large grey follicles appear. Banksia aemula resprouts from its woody base, known as a lignotuber, after bushfires.

First described by the botanist Robert Brown in the early 19th century, it derives its specific name 'similar' from its resemblance to the closely related B. serrata. No varieties are recognised. It was known for many years in New South Wales as B. serratifolia, contrasting with the use of B. aemula elsewhere.

How to grow it

In 1788, Banksia aemula was one of the first banksias to be cultivated in England, where it was illustrated in Curtis's Botanical Magazine and its rival, The Botanical Register. Its shiny green leaves, showy flower spikes, huge follicles, and wrinkled bark are attractive horticultural features. It is also a bird- and insect-attracting plant.

Trials in Western Australia and Hawaii have shown B. aemula to be resistant to Phytophthora cinnamomi dieback. It requires a well-drained slightly acid (pH 5.5–6.5) soil, preferably fairly sandy and a sunny aspect. Summer watering is also prudent, as it does not suffer water stress well. Slow-growing, the plant takes four to six years to flower from seed. It is less commonly grown than Banksia serrata. An investigation into optimum temperatures for germination found a nighttime temperature of 20–28 °C (68–82 °F), and a daytime of 24–33 °C (75–91 °F) gave best results, and recommended summer planting times.

Where it grows

Banksia aemula is found along the east coast of Australia from around 70 km (43 mi) north of Bundaberg in central Queensland down to Sydney. Specifically, its southernmost occurrence is at La Perouse on the northern side of Botany Bay. It is also found on Fraser, Moreton and North Stradbroke Islands. Almost all populations are within a few kilometres of the coast, except for one at Agnes Banks in western Sydney, and two just north and south of Grafton at Coaldale and Glenreagh, and a last around 30 km (19 mi) southwest of Bundaberg.

Other Banksia plants

Banksia acanthopoda · Prickly Banksia · Banksia acuminata · Banksia alliacea · Cactus Dryandra · Northern Banksia · Yilgarn Dryandra · Banksia archaeocarpa · Banksia arctotidis · Banksia armata var. armata · Banksia armata var. ignicida · Prickly Dryandra