How to grow Hibiscus in Australia
Two kinds of hibiscus are grown in Australian food gardens. Rosella (Hibiscus sabdariffa) is a fast, frost-tender annual shrub whose fleshy red calyces, the cups left after each flower drops, make jam, cordial and tea. The showy Hawaiian hibiscus (Hibiscus rosa-sinensis) is a warm-climate ornamental shrub. Both want sun, warmth, regular water and good drainage.
📖 Our full guide: How to Grow Hibiscus in Australia
At a glance
When to sow by region
| Region | When to sow | Regional note |
|---|---|---|
| South East Queensland | September to November | |
| Northern Rivers NSW | September to November | |
| Sydney & Coastal NSW | October to December | Sow rosella or plant hibiscus Oct to Dec. Rosella needs a long hot season, so start it early in the warmest spot; frost tender. |
| Melbourne & Victoria | November and December | Rosella as annual in warm spots only. Very narrow window. Nov to Dec sow. |
| Adelaide & SA | October and November | Plant Oct to Nov after frost in a warm sheltered spot. Water well through summer; cover young plants on frosty nights. |
| Perth & WA | September to November | |
| Tasmania | Not suited | Unsuitable. Rosella needs a long hot season. Not viable in Tasmania. |
| Canberra & ACT | Not suited | Rosella not viable in Canberra. Frost kills. |
| North Queensland | September to February | Rosella thrives. Year-round warmth ideal. |
| Darwin & Top End | All year | Year-round in Darwin. Rosella grows vigorously. |
Where to plant
Plant in full sun, with at least six hours of direct light, in well-drained soil enriched with compost or aged manure. Neither rosella nor Hawaiian hibiscus likes wet feet. Shelter from strong wind helps, as the stems are brittle and wind damages the flowers.
Rosella is easiest in warm, frost-free areas such as Queensland, northern New South Wales and the Northern Territory. In cooler southern areas it can be grown as a summer annual, planted after frost in the warmest spot, but it needs a long, hot season to crop. Hawaiian hibiscus grows well in Perth, Sydney and further north, and is harder to grow in the south.
- South East Queensland and the Northern Rivers: sow rosella or plant hibiscus from September to November.
- North Queensland: sow rosella from September to February. Darwin: rosella can be sown at any time of year and grows vigorously.
- Sydney: sow rosella or plant hibiscus from October to December. Start rosella early in the warmest spot, as it needs a long hot season.
- Adelaide and Perth: plant in October or November after frost in a warm, sheltered spot, and water well through summer. Cover young plants on frosty nights.
- Melbourne: rosella only as a summer annual in warm spots, sown in November or December.
- Canberra and Hobart: our calendar marks these as unsuitable, as frost kills rosella and the season is too short.
Choosing a variety
| Type | Notes |
|---|---|
| Rosella (Hibiscus sabdariffa) | An annual from West Africa grown for its red calyces and tart young leaves. Fast growing to about 1.5 to 2 m. Naturalised in parts of Australia |
| Native rosella (Hibiscus heterophyllus) | A tall, fast-growing native shrub of eastern NSW and Queensland, 3 to 6 m, with large white, yellow or pink flowers that feed honeyeaters. Its parts have some similar uses. Grown in Canberra and Melbourne against a warm wall |
| Hawaiian hibiscus (Hibiscus rosa-sinensis) | The large-flowered ornamental shrub, in a huge range of colours. Flowers in flushes in spring and autumn. Grown for show, not for food |
How to plant
- Enrich the bed with compost or aged manure.
- Sow rosella seed direct once the soil has warmed in spring, or start it in pots for a head start in cooler areas.
- Space plants about 1 to 1.5 m apart, as rosella grows into a bushy shrub.
- Plant Hawaiian hibiscus in spring or early summer at the same depth as in the pot.
- Water in, then mulch, keeping the mulch from touching the stems.
Watering and feeding
Water consistently, especially during hot spells, but never leave the soil waterlogged. Plants that dry out drop flowers and buds.
Rosella needs only occasional feeding with a balanced fertiliser to boost flowering and calyx production. Hawaiian hibiscus is a hungry plant: Gardening Australia recommends a citrus or hibiscus fertiliser monthly from August to March, with soil that is neutral to slightly alkaline.
Pruning and care through the year
- Hawaiian hibiscus: prune hard in September to shape it, then lightly in February. It responds well to pruning and can be clipped as a hedge.
- Rosella is an annual. Pull it out once it finishes cropping, and save some seed from the last calyces for next year.
- Keep air moving around plants in humid areas to reduce fungal problems.
- Check flowers for small black hibiscus beetles, which chew the buds.
Harvesting
Rosella is a short-day plant: it holds off flowering while the days are long and sets buds as they shorten, so calyces come from late summer into autumn. Pick the calyces when they are plump, firm and bright red, soon after the petals drop, before they turn dry and woody. Snap or cut them off; the plant keeps flowering as long as you keep picking. The young leaves are also edible, with a tart flavour, and can be added to salads or cooked like spinach.
To use the calyces, split each one and push out the green seed pod. Use them fresh, freeze them or dry them for tea.
Growing in pots
Both rosella and Hawaiian hibiscus grow well in a pot at least 40 cm wide with good drainage and a quality potting mix. Water regularly in summer and feed through the warm months. A pot lets you move hibiscus to a warm, sheltered spot in cooler areas.
Using it
Rosella calyces make the classic Queensland rosella jam, and cordial, syrup, chutney and a tart, ruby-red tea. Boil the separated seed pods in water to extract their pectin, then use that liquid when making jam.
Propagation and saving seed
Rosella grows easily from seed saved from dried pods. Hawaiian hibiscus and native rosella are usually grown from cuttings. Cuttings of native rosella give plants with more fibrous roots and longer flowering than seedlings, which makes them better for pots.
Companion planting
Hibiscus fits a warm-climate garden among other tropical plants that want the same heat, sun and regular water.
Good companions
- Tropical plants Other warm-climate plants share the same heat, humidity and watering, and together make a sheltered, humid planting.
Pests and diseases
Rosella has few serious pests. Hawaiian hibiscus attracts more sap suckers and the hibiscus beetle.
Pests to watch for
- Hibiscus beetle Small black beetles inside the flowers and buds, which chew them and make buds drop. A simple insecticidal soap spray works well.
- Aphids Clusters of small soft insects on new shoots and buds. Hose them off or squash them.
- Mealybug White, cottony clusters on stems and leaf joints, with sticky honeydew.
- Caterpillars Chewed leaves and calyces. Pick them off by hand.
Diseases to watch for
- Leaf spot Brown or black spots on the leaves in humid weather. Improve air flow and remove affected leaves.
- Dieback Stems dying back from the tips, often after wet feet, frost or damage. Prune back to healthy wood and check drainage.
Common questions
What is rosella?
Rosella (Hibiscus sabdariffa) is an annual hibiscus grown for its fleshy red calyces, the cups that form after the flowers drop. They are used for jam, cordial, syrup and tea.
When do you harvest rosella?
From late summer into autumn, when the calyces are plump, firm and bright red, soon after the petals fall. Keep picking and the plant keeps flowering.
Can I grow rosella in Melbourne?
Only as a summer annual in a warm, sunny spot, sown in late spring after frost. It needs a long, hot season, so the crop is smaller than in Queensland.
Can you eat hibiscus flowers?
Rosella calyces and young leaves are eaten. The Hawaiian hibiscus is grown as an ornamental; stick to rosella for food.
When should I prune my hibiscus?
Prune Hawaiian hibiscus hard in September for shape and lightly in February. Rosella is an annual and does not need pruning.
What are the little black beetles in my hibiscus flowers?
Hibiscus beetles. They chew the flowers and buds. Gardening Australia recommends an insecticidal soap spray made from cheap detergent diluted until syrupy.
How do I make rosella jam?
Separate the calyces from the green seed pods. Boil the pods in a little water to extract their pectin, strain, then cook the calyces in that liquid with sugar until it sets.
Sources we checked: Gardening Australia: Hibiscus; Gardening Australia: Ask It, Solve It (hibiscus beetle); Searles Gardening: Growing rosellas; Sustainable Gardening Australia: Native rosella, Hibiscus heterophyllus; Happy Valley Seeds: How to grow rosella in Australia, seed to jam.