Mountain Gum, Eucalyptus Dalrympleana 15-30cm Screening Trees

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Mountain Gum (Eucalyptus dalrympleana) aka Mountain White Gum – Fast Growing Screening Trees for Tall Evergreen Privacy

Our young Mountain Gum cell grown trees are a very good option for developing attractive, tall, informal evergreen screens cheaply. Mountain Gum holds the RHS Award of Garden Merit^[5] and its exceptional growth rate means you don’t have to wait very long to block out the eyesore.

Mountain Gum does not lend itself well to formal, clipped hedging. Its naturally light canopy^[8] is better suited to informal screening than a solid wall of foliage. Informal screening means reasonably closely planted and hardly pruned so it keeps its natural shape. To put it another way, if you have a nudist colony start-up next door, a Leylandii or other similar hedge will give you a child-friendly garden, whereas a eucalyptus screening hedge will probably make it PG (parental guidance advised)

Fast Growing Eucalyptus Saplings for Woodland, Timber and Firewood

Mountain Gum is among the eucalyptus species identified for UK short-rotation forestry, with potential for timber and woodfuel production.^[2] Its upright growth and good stem form support these uses.^[2][6]

Mountain Gum – White Peeling Bark, Evergreen Foliage and Seasonal Interest

Its smooth bark peels to reveal pale cream and white surfaces that gradually develop salmon-pink and light brown colouring.^[4]

Juvenile leaves are broad, oval-shaped and grey-green. Mature leaves are longer, narrower and darker grey-green, while new growth can have coppery tones.^[1]

Mountain Gum produces white flowers.^[1] Eucalyptus flowers provide nectar for bees and other pollinators, although flowering depends on the species and growing conditions.^[8]

Mountain Gum Growth Rate and Mature Height

Published forestry literature gives an indicative height-growth rate of 1.5–2 metres a year under suitable conditions.^[6] For the comedians out there, yes, it can grow 6 feet a year, and no, you don’t need to buy 3 pairs of shoes for it.

How Tall Does Mountain Gum Grow?

The RHS gives Mountain Gum a mature height of 12+ m x 8 m.^[1] However, several specimens growing in Britain are substantially larger.

The tallest documented specimen found in the UK reached 33.5 metres at Lydney Park, Gloucestershire, in 2015. Another reached 33 metres at Abbotsbury Subtropical Gardens, Dorset, in 2017,^[4][16] and plenty of other examples we found were at 30+m.

A 2022 professional tree survey at Langton Green, near Tunbridge Wells, Kent, recorded two Mountain Gums measuring 24 metres tall with a 10-metre crown spread, and 19 metres tall with a 12-metre crown spread.^[15] This indicates width is very roughly half the height.

Compare Mountain Gum

Mountain Gum has several advantages over other popular eucalyptus trees, although which is best depends on your priorities.

Compared with Cider Gum (Eucalyptus gunnii), Mountain Gum grows faster and produces straighter, better-formed trunks, making it a stronger choice for timber production.^[6] Forestry Commission guidance places both in the 1.5–2 metres annual growth category when young, but identifies Mountain Gum as the faster species overall.^[6][17]

Cider Gum wins on frost resistance. High-altitude Cider Gum provenances may withstand brief temperatures down to −18°C, compared with approximately −14°C for Mountain Gum.^[17]

Manna Gum (Eucalyptus viminalis) wins on speed, with Forestry Commission guidance classifying it as very fast-growing, exceeding 2 metres annually when young, compared with Mountain Gum's 1.5–2 metres.^[17]

However, Mountain Gum wins on cold tolerance. The same guidance places Manna Gum in a less hardy category, with estimated short-term tolerance around −9°C, compared with −14°C for Mountain Gum.^[17]

Mountain Gum also offers attractive white, cream and pinkish peeling bark and holds the RHS Award of Garden Merit.^[1][5] Cider Gum also holds this award, so it is not an exclusive advantage.^[7]

Mountain Gum Soil Requirements – Clay, Chalk, Loam and Drainage

The RHS lists clay, chalk, loam and sandy soils, with a preference for slightly acidic ground.^[1]

Mountain Gum has also been recorded growing on brown earth over limestone pavement in Cumbria.^[6]

What About Wet Ground?

Mountain Gum grows in moist, well-drained and poorly drained soils. However, it is best suited to ground where excess water can drain away. Avoid permanently waterlogged or flooded sites.^[1][2][8]

Mountain Gum requires full sun.^[1]

Mountain Gum Hardiness – Frost, Coastal Conditions and Drought

Mountain Gum can tolerate temperatures down to approximately −14°C for short periods, but prolonged cold spells below −6°C to −9°C may cause damage.^[1][6]

Can Mountain Gum Grow Near the Coast?

Mountain Gum is suitable for sheltered coastal gardens and tolerates salt spray. Avoid exposed beachfront locations.^[1][2]

Is Mountain Gum Drought Tolerant?

Mountain Gum can suffer reduced growth during drought. Severe drought can cause foliage and branches to die back, particularly in smaller trees.^[9][10]

Coppicing and Pollarding Mountain Gum – Managing Height and Form

Mountain Gum is suitable for both coppicing and pollarding.^[3]

Coppicing Mountain Gum

Coppicing means cutting the tree close to ground level to encourage new stems and juvenile foliage.^[3] The RHS advises:^[3]

• Cutting to approximately 5–7.5 cm above ground or to previous coppicing stubs.
• Working in February or March, before active growth.
• Repeating the process annually or every few years, depending on the aim.

From approximately two years old, Mountain Gum can also be trained as a multi-stemmed tree by cutting its main stem and selecting three or four well-spaced replacement stems.^[3]

Start coppicing while trees are relatively young. Large trees never previously coppiced may fail to regrow after severe cutting, and new shoots can snap in strong winds.^[3]

Pollarding Mountain Gum

Pollarding involves repeatedly cutting branches back to established points on a permanent trunk, commonly around 2 metres above ground.^[3] It requires ongoing maintenance; work at height may need a qualified tree surgeon.^[3]

Choose coppicing over pollarding when you want Mountain Gum to:

• Grow as a bushy, multi-stemmed plant rather than a tree with a clear trunk.
• Produce more attractive, rounded juvenile foliage.
• Provide leafy growth closer to ground level, making it more useful for low-level screening.
• Be easier and cheaper to maintain, as cutting is done near ground level rather than at height.

Pollarding is better when you want to retain a clear trunk and keep the foliage above head height.

Both methods control tree size, but coppicing is generally easier to carry out yourself.^[3]

Mountain Gum Roots, Animal Safety, Pests and Diseases

Mountain Gum Roots and Buildings

Eucalyptus is a high-water-demand tree group. On shrinkable clay, moisture loss in dry weather can contribute to ground movement and subsidence.^[12] Roots may also enter existing defects in underground drains and possibly block them as most tree roots do with defective drains.^[12]

Is Mountain Gum Toxic to Animals?

Let the games begin. The short answer is, if someone knows for sure by running a study and researching it, they didn't put it anywhere we could find as of October 2026.

Is Mountain Gum (Eucalyptus dalrympleana) poisonous to animals? The scientific evidence is less conclusive than you might expect. There are reasons to be cautious, but the research we found does not establish that Mountain Gum foliage is poisonous to livestock, or that it is safe for them to eat.

The Evidence That Mountain Gum May Be Toxic

The ASPCA classifies eucalyptus as toxic to dogs, cats and horses because of essential oils, including eucalyptol. Reported symptoms include salivation, vomiting, diarrhoea, depression and weakness. However, this classification applies to eucalyptus generally, rather than being based on a toxicity test specifically involving Mountain Gum.^[11]

There is also the question of cyanide. Some eucalyptus species contain compounds that release cyanide when their leaves are damaged or chewed. A scientific paper published in 2006 included Mountain Gum among species previously believed capable of releasing cyanide. However, that paper did not present measurements confirming cyanide production in Mountain Gum or establish a toxic concentration for the species.^[22]

The Evidence Against Confirmed Cyanide Toxicity

In 2008, researchers examined approximately 420 eucalyptus species for their ability to release cyanide. Mountain Gum was not included among the confirmed cyanide-producing species. However, the published paper does not establish whether Mountain Gum was individually tested and found negative. Nor does it establish that its foliage is harmless to animals.^[23]

There is also evidence of Mountain Gum being grown on Australian livestock farms. A five-year forestry study included Mountain Gum in plots that sheep and cattle briefly entered, causing browsing damage to the mixed tree plantings. However, the study did not establish how much Mountain Gum foliage, if any, the animals consumed, and was not designed to investigate poisoning. It therefore cannot establish that the species is safe to eat.^[20]

So, Is Mountain Gum Safe Around Animals?

There is insufficient species-specific evidence to give Mountain Gum a clean bill of health as animal feed, but equally, the sources examined do not demonstrate that eating its foliage causes poisoning.

Our advice is to prevent dogs, cats, horses, sheep and cattle from eating Mountain Gum leaves or cut branches until reliable evidence establishes their safety.

Unfortunately, science has not yet given us a definitive yes or no. We would rather tell you that than invent one. You see why we didn't give you a yes or no.

Mountain Gum Pests and Diseases

Possible problems listed by the RHS include eucalyptus gall wasp, eucalyptus sucker, silver leaf, oedema and honey fungus.^[1]

• Eucalyptus gall wasp can cause raised leaf swellings and leaf fall, but generally does not harm long-term vigour.^[13]
• Eucalyptus sucker can produce honeydew and sooty mould; serious damage is unusual.^[14]

These are possible problems, not inevitable ones.

Other Allegedly Interesting Facts About Mountain Gum

Mountain Gum can also be grown for its attractive cut foliage. Coppicing encourages the rounded juvenile leaves that are popular in flower arrangements.^[3][8]

its peeling bark can also be used as kindling to help light fires, giving it another practical use alongside firewood production.^[24]

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