Also known as Flowering Gum · 14 saves
Corymbia
Corymbia, the genus most gardeners know as flowering gum. We track 13 varieties; the ones most used by real gardeners.
The 13 most-saved Corymbia varieties
5 species of Corymbia
Each one is a parent of the varieties above.
Track your Corymbia in Sow
Save the Corymbia you grow and get care reminders timed to your zone.
How to grow Corymbia
Whats common across all Corymbia varieties in our catalog — drawn from the care records of the 13 most-grown of them.
The Corymbia year
- PruneAugust and September100% of varieties
Lightly prune to shape or remove damaged wood, avoiding cuts into old bare wood.
- FertilizeMarch and April100% of varieties
Apply a low-phosphorus native slow-release fertiliser to support growth.
- Check for PestsJune and July100% of varieties
Inspect new growth for bright yellow-orange pustules of myrtle rust, especially during warm, humid weather.
- MulchMay and November54% of varieties
Apply a fresh layer of organic mulch around the root zone to protect against temperature extremes.
- PlantMarch, April, September and October38% of varieties
Plant out young container-grown trees into warm, highly permeable soil.
Do
- Use a low-phosphorus native fertiliser sparingly in early spring.
- Water deeply during extended dry periods to maintain vigor, especially while the tree is establishing.
- Apply a low-phosphorus native-specific fertiliser sparingly in early spring.
- Ensure the planting site has adequate sub-surface drainage, even when planting near wet areas.
- Plant grafted specimens to ensure predictable flower colour and root-rot resistance.
Avoid
- Do not prune heavily into old, bare wood, as this can severely damage or kill the tree.
- Do not plant in permanently stagnant, waterlogged sumps without drainage, which leads to root rot.
- Do not use standard high-phosphorus garden fertilisers.
- Do not apply standard high-phosphorus fertilisers, which cause nutrient toxicity.
What goes wrong with Corymbia
| Problem | What you'll see | What to do |
|---|---|---|
| Borers | Holes in branches, exudation of sap or frass, and dieback of affected limbs. | Prune out heavily infested branches cleanly and maintain plant vigor. |
| Possums and cockatoos | Chewed bark, broken branchlets, and stripped flower buds. | Use physical tree guards on young specimens if local wildlife pressure is high. |
| Possums and Cockatoos | Chewed flower buds, stripped bark, or broken branches. | Install physical tree guards around young trunks and accept minor canopy damage on mature trees. |
| Psyllids | Leaf distortion and sugary excretions known as lerps on the foliage. | Spray with insecticidal soap or horticultural oils if infestations are heavy. |
| Myrtle rust | Bright yellow pustules and distorted young leaves, shoots, and flower buds. | Prune out and destroy infected material, then apply registered fungicides under local guidelines. |
| Myrtle Rust (Austropuccinia psidii) | Purple-brown spots on leaves, stems, and buds, followed by bright yellow powdery spores. | Prune off infected parts where practical and apply registered fungicides in accordance with local state agricultural guidelines. |
| Phytophthora Dieback (Phytophthora cinnamomi) | Root rot, sudden or progressive wilting, dieback of the canopy, and plant death. | Ensure flawless drainage; plant in elevated beds or mounds; apply preventive treatments like phosphite where high risk is present. |
Making more Corymbia
Grafting
- Select a compatible rootstock such as Corymbia maculata or C. ptychocarpa.
- Take a scion from a mature, desired flower-colour Corymbia ficifolia.
- Perform a cleft or whip-and-tongue graft near the base of the rootstock.
- Secure the graft union and maintain high humidity until the union heals.
Seed
- Collect mature, woody barrel-shaped fruits after flowering and place them in a paper bag until they open to release the seeds.
- Sow seeds on the surface of a moist, free-draining native seed-raising mix.
- Lightly cover with a thin layer of fine grit or vermiculite and keep moist in a warm, bright position.
- Prick out seedlings into individual pots once they develop their first set of true leaves.
Corymbia questions
How many types of Corymbia are there?
The Sow catalog tracks 13 distinct Corymbia varieties. The most popular — ranked by 14 real gardeners — are shown first above.
What zones does Corymbia grow in?
Across its varieties, Corymbia covers USDA Zones 9–10. Individual varieties differ — each plant page lists its exact range, and Sow filters the catalog to your zone automatically.
When does Corymbia bloom?
Most Corymbia varieties bloom in summer, winter, late spring. Staggering early, mid, and late varieties extends the genus's season in one bed.
Which Corymbia should I choose?
Start from the most-saved varieties above — popularity across thousands of gardens is a strong signal of reliability — then filter by your zone and sun. In the Sow app you can preview any of them in a photo of your actual yard before you buy.