What do you think of when you hear the word ‘hibiscus’? Perhaps it’s Nanna’s garden, a Balinese sarong or a bright Hawaiian shirt? Despite its exotic, tropical associations, Australia has over 100 species of native hibiscus that occupy just about every ecosystem, from rainforest to desert.
Probably the two most common species of hibiscus in SEQ are Native Rosella (Hibiscus heterophyllus) and Cottonwood (Hibiscus tiliaceus). Native Rosella is a shrub with variable leaves ranging from simple to lobed with prickly stems. Its flowers are white with pink markings (although can be yellow). This species can often be found along rainforest margins and waterways. The Cottonwood is a spreading tree along mangroves, estuaries and dunes. It has yellow flowers and heart shaped leaves.
Bridgette Chilli Davis is a proud Murulla woman of Jhdungah Country, within the Kabi Kabi Nation and language group, Sunshine Coast. Bridgette was born on country and raised by her grandmother Pauline Chilli Davis, who was the matriarch of her family and the Murulla women of her community. Pauline taught Bridgette the traditional uses and significance of the
Gh-gung (Cottonwood) and Bhd-idi (Native Rosella).
Gh-gung (Cottonwood) is a mother tree for Jhdungah Murulla women as it is highly resourceful and provider of shelter. Bhd-idi (Native Rosella or White Rosella) is a short-lived pioneer. Both species were harvested extensively by Jhdungah Murulla women for weaving fibre to make fishing nets, baskets, ceremonial dress and mats. The women harvested smaller branches, stripped the bark, soaked them in water until they were fibrous, then dried them out before adding different dyes (berries and ochre) to colour them, and finally weaving the fibres.
Gh-ung was also used to make fire. The (female) Gh-gung base was placed at the bottom, while the (male) Xanthorrhoea or grass tree flower stalk was used as the fire stick. Bridgette explains “You place male on female and rub to make fire. It’s all in balance, everything in our culture is in balance.”
Bridgette fondly remembers her grandmother taking her down to Cotton Tree near Maroochydore and feeding her the young buds and flowers of the Gh-gung. She notes that the larvae of the Hibiscus Harlequin Bug were also eaten traditionally but confesses that she hasn’t tried them personally yet.
Jhdungah Murulla women were exceptional at catching seafood and could be recognised by one shortened pinky finger. At a young age, their smallest finger was bound by web of the Golden Orb Spider. When the tip of the finger fell off the girl was ready for womanhood and marriage. The shortened finger was useful for making the nets, baskets and ceremonial dress from the native hibiscus species as it wouldn’t get caught in the fibres.
When the Gh-gung is flowering in spring and early summer, the Jhdungah Murulla people would know that is was a good time to catch River Whiting, which have yellow on the fins the same as the Gh-gung flowers. The fish was cooked and served in the Gh-gung flowers and leaves and eaten together.
Modern culinary uses for Native Rosella are widely varied. Native Rosella buds can be cooked and made into jam. Petals and buds can be eaten raw, however the flavour is very mild and best used as a colourful ornament in salads. Flowers can be stuffed, made into fritters or brewed as a tea. Leaves are recorded to taste like sorrel and the roots like woody parsnips – an incredibly versatile vegetable. Likewise, the young leafy shoots of Cottonwood can be eaten as vegetables.
Native Rosella was one of the earliest native hibiscus to be grown in Europe from seed collected in Australia. Cottonwood was used like cork to seal cracks in boats. Medicinally, Cottonwood has been used to treat fevers and menstrual issues by making a tea from bark and roots. Caution should be taken when handling Native Rosella as there are irritant hairs on the seed capsule.
Now, if I’ve lost you with too many entomological references allow me to inject some scandal into the article. The Native Rosella has been used in film and television as a visual substitute for cannabis bushes, as the deeply lobed leaves resemble the illicit plant.
You’ll probably notice a lot of insect activity on native hibiscus species on your property. These insects can cause flower buds to drop prematurely, but it’s important to remember they are a natural part of the ecosystem. Insects are considered the main hibiscus pollinators, including bees that emerge from the flowers with obvious pollen attached.
The Hibiscus genus has been under taxonomic review in recent years through the work of botanist Dr Todd McLay. Dr McLay has been using modern DNA sequencing techniques that have only been developed in the last 5-10 years. Traditional DNA sequencing takes the same part of a genome for all different species and analyses the difference. With this new technique, botanists are now able to sample 100s of genes instead of just one. Where traditional morphology is very complex, such as in the genus Hibiscus, DNA sequencing can help complement taxonomy.
Dr McLay has discovered 40 new species of hibiscus through his research.
Whilst field work was vital, 90% of specimens came from herbarium collections. This was challenging and involved a lot of detective work including looking at scraps of leaves sent around the world and handwritten labels over 150 years old. Dr McLay even examined specimens from the Bourke and Wills expedition.
Hibiscus taxonomy is a work in progress and Dr McLay isn’t convinced that our local hibiscus, H. heterophyllus is just one species. Differences include the colour of the flower, spiny hairs on stems and leaf size. He plans to do DNA sequencing and look at herbarium specimens to solve this conundrum.
He believes the matter is complicated by a large number of cultivars that have planted in bushland settings. A great reminder to always plant local provenance seedlings that are consistent with the regional ecosystem/s on your property.
References and Further Reading
Aluri J, et al. (2020) Pollination ecology of Hibiscus tiliaceus, an evergreen tree species valuable in coastal and inland eco-restoration. Transylvanian Review of Systematical and Ecological Research, 22:2, 47-56.
Low, T (1991) Wild Food Plants of Australia. Harper Collins.
Williams G (2020) The Invertebrate World of Australia’s Subtropical Rainforests. CSIRO Publishing.
www.sown.com.au (Save our Waterways Now)
Article and photos by Danielle Outram
Land for Wildlife Officer
Sunshine Coast Council