| Botanic name | Eucalyptus mannifera |
| Other names | Brittle gum, mottled gum, red-spotted gum |
| Main Origin | Southeastern Australia |
| Mature size | 4 – 10 m x 8 – 20 m (w x h) |
| Mature form | Medium to large tree with an open, spreading canopy |
| Foliage | Narrow, lance-shaped, slightly curved, grey-green |
| Growth rate | Moderate |
| Position | Full sun |
| Soil | Adapts to most soils |
| Water | Occasional deep watering during extended dry periods |
| Climate | Semi-arid, Mediterranean, temperate, mild subtropical |
| Flower | Small, cream-white, from early summer to autumn |
| Use | Feature specimen, windbreak, avenue planting |
| Notes | High frost tolerance |
IN THIS ARTICLE
Overview
There is something quietly enchanting about Eucalyptus mannifera, commonly known as Brittle Gum. In the shifting daylight, its bark seems to glow – smooth and pale, sometimes ghostly white, other times washed with soft greys.
This tree doesn’t shout for attention, yet it holds it effortlessly. Slender, upright, and graceful, Brittle Gum brings an air of elegance to streetscapes and gardens. Its beauty lies in this balance: striking enough to notice but subtle enough to never overwhelm.
Origin and distribution
Eucalyptus mannifera is native to southeastern Australia. It is a common sight in dry forests and woodlands, on stony, elevated terrains like hills or tablelands.
Valued for its ornamental beauty, adaptability, and resilience, Eucalyptus mannifera is widely cultivated across Australia, particularly in the southern and eastern regions, with Canberra being a notable example. It is also cultivated abroad, including in New Zealand.
Growth and care
Eucalyptus mannifera thrives best in temperate climates with dry summers and cool and cold winters. It can also adapt to Mediterranean, semi-arid or mild subtropical zones with adequate rainfall and humidity.
While its cold tolerance varies slightly based on subspecies, Eucalyptus mannifera can generally withstand cold temperatures down to -12°C with high frost resistance. It performs exceptionally well in regions that experience heavy frosts and even occasional light snowfalls.
It can handle the cold about as well as the Silver-leaved Mountain Gum (Eucalyptus pulverulenta), though it falls short of the hardiness shown by true alpine species like the Snow Gum (Eucalyptus pauciflora) and Cider Gum (Eucalyptus gunnii).
Young trees require regular watering to develop a strong, deep root system in their first 1 – 2 years. Established trees are highly drought-tolerant and can withstand prolonged dry spells.
The species is often found on shallow, rocky, and heavier clay soils. However, it adapts to most soils that are slightly acidic to neutral. The species thrives in infertile or moderately fertile soils with good drainage, although it has been shown to tolerate winter waterlogging.
While it tolerates poor soils, incorporating some coarse organic matter, such as compost or well-rotted pine bark, into heavier soils can improve their structure and drainage.
In smaller urban or suburban spaces, pruning is a usual practice to manage its size as the tree can grow over 20 metres in height. Also, as its common name suggests, it can be prone to wood snapping, making it a potential hazard if its branches are not properly managed.
For mature trees, coppicing (cutting at the tree base) and pollarding (cutting at a certain height of the trunk) are both suitable. The species possesses a lignotuber and the epicormic growth ability, making it highly responsive to severe pruning.
For young trees, formative pruning (removing lower competing branches) is common to establish a strong central leader and a balanced, aesthetically pleasing canopy.
Features
Eucalyptus mannifera typically grows as a small to medium-sized tree, reaching a height of 8 – 20 metres. It develops an open, spreading, and somewhat pendulous canopy. The overall form is graceful and elegant with a single, straight trunk that branches into an open, airy structure.
Its main branches ascend and then spread horizontally, sometimes developing a slightly contorted character, adding visual interest. Its canopy is open and airy, creating filtered or dappled shade.
The most distinctive feature is its smooth, powdery white, cream, or pale grey bark, often with patches of salmon-pink or red. This gives rise to its other common names, including Mottled Gum and Red-spotted Gum.
Eucalyptus mannifera develops narrow, lance-shaped leaves that are pale green or grey-green and may be slightly curved.
From summer to autumn, small, cream or white flowers emerge in clusters amongst foliage, offering a valuable nectar source for native birds and bees. Small, cup-shaped gumnuts follow.
Eucalyptus mannifera ‘Little Spotty’
Eucalyptus mannifera ‘Little Spotty’ is a popular and valuable cultivar of Brittle Gum. It is specifically selected for characteristics that make it more suitable for smaller gardens and urban landscapes.
- Compact size: The cultivar typically reaches a height of 5 – 8 metres with a spread of 3 – 7 metres, highly suitable for smaller gardens.
- Enhanced form: The tree develops a more rounded, compact canopy than its parent’s more open and spreading counterpart. It tends to maintain a neater appearance.
- Striking bark: Like its parent, it possesses beautiful, smooth, powdery white to pale grey bark that sheds in patches to reveal shades of cream, pink, and red.
- Excellent adaptability: ‘Little Spotty’ inherits the outstanding resilience of the parent plant, including high frost resistance, exceptional drought tolerance, and flexibility with growing substrates, including rocky and poor clay soils.
