Also known as Grass Tree · 3 saves
Xanthorrhoea
Xanthorrhoea, the genus most gardeners know as grass tree. We track 4 varieties; the ones most used by real gardeners.
The 4 most-saved Xanthorrhoea varieties
4 species of Xanthorrhoea
Each one is a parent of the varieties above.
Track your Xanthorrhoea in Sow
Save the Xanthorrhoea you grow and get care reminders timed to your zone.
How to grow Xanthorrhoea
Whats common across all Xanthorrhoea varieties in our catalog — drawn from the care records of the 4 most-grown of them.
The Xanthorrhoea year
- FertilizeMarch and April100% of varieties
Apply a low-phosphorus native fertiliser sparingly around the base during active growth.
- Check for PestsJanuary, June, July and December100% of varieties
Inspect the central crown and base for signs of rot or water pooling, ensuring drainage remains completely clear.
- PruneSeptember and October75% of varieties
Clear dead foliage carefully from the upper trunk if a clean look is desired, but never cut into the green crown.
- MulchOctober50% of varieties
Apply a thin layer of inorganic gravel or rock mulch around the base, keeping it clear of direct contact with the stem.
Do
- Ensure the soil drains rapidly and completely after rainfall.
- Clear dead leaves carefully from the upper trunk if a clean trunk profile is preferred.
- Use coarse, inorganic gravel mulches to keep the collar dry.
- Apply low-phosphorus native fertilisers very sparingly during active growth.
- Ensure absolute soil drainage to prevent root rot and Phytophthora dieback.
Avoid
- Never water directly into the central crown or allow water to pool at the growing point.
- Never prune or shear back the living green leaves of the crown.
- Never cut into the trunk or old, resin-cemented leaf bases.
- Never attempt to transplant mature, wild-collected specimens.
What goes wrong with Xanthorrhoea
| Problem | What you'll see | What to do |
|---|---|---|
| Scale insects | Small brown or white bumps on the leaf bases, accompanied by sooty mould. | Apply horticultural oil during cooler hours if infestations become severe, though healthy plants rarely suffer significant damage. |
| Oil-based chemical burn | Severe phytotoxicity, rapid dieback, or death when oil-based sprays or certain herbicides are applied directly onto the growing center. | Avoid spraying oil-based insecticides or systemic herbicides near or onto the foliage crown. |
| Borers | Entry holes in the trunk, sawdust-like frass, and localized stem dieback. | Maintain high plant vigour and carefully remove heavily infested sections without damaging the main growing point. |
| Phytophthora dieback | Root rot, sudden foliage collapse, and crown death. | Ensure pristine soil drainage, practice strict hygiene, and apply registered phosphite treatments if necessary. |
| Fungal collar and crown rot | Rotting and softening at the growing apex. | Keep the crown dry, avoid overhead watering, and use coarse gravel mulches around the base. |
| Phytophthora dieback (Phytophthora cinnamomi) | Gradual decline, root rot, crown death, and ultimate collapse of the plant. | Ensure absolute soil drainage, avoid introducing infected soil, and use preventative phosphite treatments in high-risk settings. |
Making more Xanthorrhoea
Seed
- Sow fresh seed into a well-aerated, sandy native seed-raising mix.
- Keep the medium lightly moist but never waterlogged, placing the tray in a warm, semi-shaded position.
- Prick out seedlings into individual deep pots once they are large enough to handle, taking care not to disturb the young roots.
- Grow on in containers for several seasons until a robust root system is established before planting out.
Xanthorrhoea questions
How many types of Xanthorrhoea are there?
The Sow catalog tracks 4 distinct Xanthorrhoea varieties. The most popular — ranked by 3 real gardeners — are shown first above.
What zones does Xanthorrhoea grow in?
Across its varieties, Xanthorrhoea 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 Xanthorrhoea bloom?
Most Xanthorrhoea varieties bloom in autumn, winter. Staggering early, mid, and late varieties extends the genus's season in one bed.
Which Xanthorrhoea 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.