Hibiscus ‘Gold Haze’ is a selected bright yellow flowering hybrid of Hibiscus divaricatus (gold form) and H. heterophyllus (gold form). Both these plants are tall shrubs but can grow to 5 to 7 m tall and both preferring warm, moist environments.
H. heterophyllus is found from the Lockhart River at the very tip of Queensland, down through eastern and central New South Wales
H. divaricatus is found in Queensland, the Northern Territory, and in northern parts of Western Australia.
H. ‘Gold Haze’ has prickly branches, the prickles short, sharp and plentiful.
The leaves are simple, lanceolate or 3-lobed, with serrate margins, up to about 15 cm long by 10 cm wide. Both sides of the leaves are prickly, like the branches.
It has large, showy, bright yellow flowers to about 8 to 10 cm in diameter with a red stripe surrounding the petal spot. With Hibiscus plants, the flowers only last for a day or so.
This author has been growing H. ‘Gold Haze’ for many years, in a garden in northern Sydney and found it to be a reliable and fairly tough plant once established. Growing it this far south requires some protection from frost and I am fortunate that where I have it growing it is protected. They grow to about three to four metres high with a similar spread and produce their flowers in spring through to late autumn. The plant is growing in a thin layer of topsoil over a clay sub soil and received little additional watering after the first year or so. They grow best in full sun, good drainage and a mulch to ensure a cool root run. The only maintenance required is to prune them back by about a third in spring, when the weather warms up. Pruning in winter is not a good idea, as the plant may be lost in the cold weather.
Since 2009, I have removed the plant as the position it was in became too shady and also it grew far too tall for my smallish garden and required constant pruning (which only made it grow faster, especially in wetter years).
I would only recommend that plant for a larger garden and grow it as a specimen tree in full sun, with some moisture.
There are many Australian Hibiscus species and they deserve to be more widely grown in our gardens especially if you are trying to create a tropical effect or just require bright and colourful flowering plants.
The only pest encountered, if it can be called that, was a season of many, very colourful, Harequin bugs that depend on the sap they suck from species such as hibiscus. The damage is rarely serious and their colours are so spectacular that they can even be considered desirable.
From cuttings, take from a healthy specimen in late winter/early spring in order to retain the characteristics of the cultivar.
From seeds, it helps to abrade the surface with sandpaper as this quickens germination. However, seedlings may not come true-to-type.
Note: the fruit is covered in hairs that may cause severe skin irritation. Sticky tape stuck onto the skin and then pulled off appears to be the easiest and most effective way to remove these irritant hairs as well as wearing gloves and using tweezers when extracting seed.
Hibiscus is a widespread genus of the family Malvaceae, consisting of 250 species world-wide, ranging from tropical to temperate regions. Of these species, 35 are native to Australia, and are largely restricted to the central East Coast up to far north Queensland.
Hibiscus species are likely killed by fire and regenerate from the seedbank.
Hibiscus – from the Greek Yvískos (Yβίσκος) meaning “Mallow” – a common name often used for species in this genus and broader plant family.
‘Gold Haze’ – named for the large deep yellow flowers.
Australian Native Hibiscus Hybrids and Crosses as at December, 2011: http://www.hibiscus.org/species/hybridscrosses.php
Some Magnetic Island Plants – Hibiscus divaricatus profile page https://somemagneticislandplants.com.au/native-hibiscus
Australian National Botanical Garden – Hibiscus heterophyllus profile page https://www.anbg.gov.au/gnp/interns-2002/hibiscus-heterophyllus.html