Hedera helix 'Thorndale' (Thorndale English Ivy)


Michael's Opinion

Great specimen if used as a vine or understory plant. Can become problematic if not pruned and cared for correctly. Winter burn is common in South Western Ontario. That said this plant has fallen out of favour with me since it can become invasive, is a vole magnet and can suffer from severe wilt and winter necrosis. It is best kept in planting beds where if it escapes it may be decapitated by the lawn mower.

Botanical Information

FamilyAraliaceae
GenusHedera
Specieshelix
Cultivar'Thorndale'
CategoryWoody
TypeVine
Pronunciation

Details

USDA Hardiness Zone3-9
USDA Hardiness Ref.
Canadian Hardiness Zone4a–8b
Canada Hardiness Ref.
RHS Hardiness Ref.
Temperature (°C)-34
Temperature (°F)-30
Height15-20 m
Spread15-25 m
GrowthFast
Flowering PeriodMay

Description and Growing Information

General DescriptionAn evergreen vine that grows as a groundcover but will climb. Attractive dark green leaves. Grows rapidly and may be considered invasive, caution in planting is urged. All parts of the plan contains toxins and ingestion of large quantities can cause sever poisoning in both humans and animals. The sap may also be an irritant to some. The berries which are toxic are seldom consumed since they are quite bitter.
ID CharacteristicCompared to Baltic Ivy, ‘Thorndale’ boasts attractive dark green leaves that are a bit smaller, have a much more prominent central lobe, and display creamy white leaf veins. It may climb but is usually grown as a ground cover plant.
ShapeHorizontal, rooting at nodes, can climb as a vine.
LandscapeGood ground cover with many uses. Ideal in heavy shade and can look especially nice when given proper cultural conditions. Grown to best effect when allowed to climb trees or buildings; Plant will become quite woody, and leaf morphology different in adult form. At points further south this plant may become invasive.
PropagationCuttings can be rooted any time of the year using 1000 to 3000 ppm IBA-quick dip.
CultivationTransplants readily; Rich, fairly moist well drained soils. Full sun or heavy shade. Protect from winter sun and wind to prevent leaf necrosis. May require considerable pruning; tolerates acid and alkaline soil; salt tolerant.
PestsBacterial leaf spot (Xanthomonas) and canker, leaf spots, powdery mildews, blight, aphids, caterpillars, mealy bugs, scales, and two-spotted mite. Subject to necrosis, although blight in Ontario seems to be the major problem.
Notable SpecimensThe University of Western Ontario, London, Ontario.
HabitatHorticultural origin.
Bark/Stem DescriptionOn adult forms, bark is light brown, rigged and furrowed. On young growth stems are often green to black.
Leaf DescriptionDark green and often lustrous above, often with whitish veins on juvenile leaves; mature leaves may appear lighter in colour and more pointed in form.
Flower DescriptionOnly occuring on adult forms; greenish white in globose umbels; present in late summer to autumn.
Fruit DescriptionBerry like, black drupe, 0.6 mm across, containing 2-5 seeds; seeds apparently poisonous.
Colour DescriptionDark green leaves that display creamy white veins. On adult forms the leaves are lighter in colour. Bark is dark brown or sometimes reddish-brown.
Texture DescriptionSmooth texture on juvenile leaves, and more rigged texture on mature leaves.

Photographs