- Mature height
- 15m to 30m (approx.)
- Mature width
- 8m to 12m
Eucalyptus robusta is the eucalypt to plant where the ground stays wet. Swamp Mahogany tolerates periodic inundation and heavy clay that would kill most trees, while producing masses of cream nectar-rich flowers through winter and spring that are a critical food source for gliders, flying foxes and honeyeaters.
Eucalyptus robusta grows fast at 1 to 1.5 metres per year, reaching 15 to 30 metres tall and 8 to 12 metres wide, with thick spongy red-brown bark that persists to the small branches. It is a tree for parkland, rural properties, revegetation and large civic landscapes rather than suburban gardens.
This Australian native grows in full sun, tolerates light to moderate frost once established, and handles coastal exposure and salt-affected ground. Once away it needs no intervention, which is why it is a standard choice for large-scale habitat and shelterbelt planting.
Frequently Asked Questions
About Eucalyptus robusta
How big does Eucalyptus robusta grow?
Swamp Mahogany reaches 15 to 30 metres tall and 8 to 12 metres wide. It is a large tree and should be sited on acreage, parkland or revegetation sites rather than a suburban block.
Does Eucalyptus robusta tolerate wet soil?
Yes. This is its defining strength. It handles periodic waterlogging, heavy clay and seasonally inundated ground that would kill most other eucalypts.
How fast does Swamp Mahogany grow?
Very fast, at 1 to 1.5 metres per year in suitable conditions. It is often used where quick canopy cover or habitat replacement is needed.
When does it flower and what feeds on it?
Cream flowers appear through winter and spring. They are a key nectar source for honeyeaters, lorikeets, gliders and flying foxes, particularly in the leaner winter months.
Is Eucalyptus robusta an Australian native?
Yes. It is native to the coastal swamps and estuarine margins of eastern Australia and is widely used in habitat restoration along that range.
Is it suitable for coastal sites?
Yes. It tolerates coastal exposure and salt-affected ground well, which is why it appears naturally in estuarine and back-dune positions.
How far apart should I plant Eucalyptus robusta?
Plant 6 to 8 metres apart for a shelterbelt or revegetation planting, and at least 10 metres from buildings, services and paving given its eventual size.