Eucalyptus gunnii f. hook (Ecualyptus gunnii)


Michael's Opinion

One of the hardiest species of Eucalyptus. Its wood, nectar, menthol-scented oil and gorgeous glaucous foliage have numerous economical and commonplace uses.

Botanical Information

FamilyMyrtacaeae
GenusEucalyptus
Speciesgunnii
Formahook
CategoryWoody
TypeTree (evergreen)
ReferencesSibley, David Allen. The Sibley Guide to Trees. New York: Random House Inc, 2009. P.106 Print. Stuart, Malcom. 1985. The Encyclopedia of Herbs and Herbalism. London, GB: Orbis Publishin. Print.
OriginSouthern Australia (Tasmania).

Details

USDA Hardiness Zone7b - 11a
USDA Hardiness Ref.
Canadian Hardiness Zone7b
Canada Hardiness Ref.
RHS Hardiness ZoneH5 - H1c
RHS Hardiness Ref.
Temperature (°C)(-12) - 7
Temperature (°F)10 - 45
Height25-30 m (if not pruned)
Spread10 m
GrowthFast
Flowering PeriodJuly, August, September, October

Description and Growing Information

General DescriptionA fast growing, medium sized evergreen tree or large shrub. Visually appealing peeling bark, rich menthol scented foliage and clusters of white flowers.
ID CharacteristicEasily identified by its peeling grey to cream coloured bark, rounded and brightly coloured glaucous juvenile foliage. Unmistakably strong menthol-scented oils emitted from the foliar oil glands and its white inflorescence flower clusters that resemble 'pom poms'.
ShapeMedium-sized, columnar and upright when left to grow without maintenance or pruning.
LandscapeA cold hardy evergreen quickly growing in popularity, is commonly used as an ornamental tree/specimen. Often planted as an accent plant/shrub or maintained as a patio tree.
PropagationPropagate by seed. Seeds require a moist and cold stratification (35 -40°F) for a period of 6-8 weeks prior to planting. Use light, non-compacting and neutral pH soil. The seed should germinate within a few weeks. Eucalyptus cuttings are difficult to root, therefore is not the favoured method of propagation.
CultivationWell-drained, neutral to slightly acidic soil with full sun. Drought tolerate once established. A shallow-rooting plant, thus does not favour any root disturbance.
PestsEucalyptus gall wasps attack during the spring and can cause a large amount of leaf loss, leaving the plant vulnerable. Susceptible to honey fungus and leaf beetle.
Notable SpecimensThe Royal Botanical Gardens, Edinburgh, Scotland.
HabitatHigh elevations in Tasmania, South Wales, and Victoria, Australia, and alpine regions such as Tasmania's central plateau at an elevation of 1,000 - 1,200 m above sea level.
Bark/Stem DescriptionBeautiful and distinctive bark, smooth to the touch and varies in colour from grey-green to cream occasionally brown with a spots of pink. The bark peels off in large pieces, revealing new bark underneath which can vary from a yellow-green to light grey in colour.
Flower/Leaf Bud DescriptionEucalyptus buds form in clusters on single stalks. The individual bud consists of a bell shaped capsule called an operculum and a cap on top called a calyptra that is shaped like a 'Hershey Kiss'. The operculum is made up of fused petals, sepals, or both.
Leaf DescriptionJuvenile foliage is oppositely arranged, with a cordate blade, entire leaf margin and obtuse apice, a silver-blue in colour. Mature foliage is very waxy in appearance and dark green. Both juvenile and mature foliage is covered in oil glands which secrete a scent similar to menthol.
Flower DescriptionThe flowers are arranged as an umbel inflorescence in clusters of 2 or 3, very much resembling pom-poms. They are white in colour and a very abundant source of nectar for bees.
Fruit DescriptionThe fruit consists of a bell shaped capsule called an operculum. It varies in colour from green to grey-blue. It is approximately 10 mm long and 5 mm wide.
Colour DescriptionIts peeling bark ranges from a dark grey-green to creamy white. The new bark is often creamy-white to yellow-green. Juvenile foliage is glaucous, showing and eye-capturing silvery, green-blue colour. Mature foliage is dark green with hints of greys and blues. Seed capsules are light to dark brown and flowers are white in bloom.
Texture DescriptionGenerally a smooth textured plant.

Photographs