London plane

London plane: how do you recognise it?

Habit

Large tree of 25–40 m with a broad, domed crown; can be kept small as a pleached or roof-trained tree.

Leaf

Alternate, palmately lobed with 3–5 lobes, 12–25 cm. The base of the leaf stalk is hollow and encloses the bud.

Bark

Peels off in large patches, creating a mottled pattern of grey, green and yellow.

Fruit

Hanging balls 2–3 cm across, often in pairs, which break up in winter into fluffy seeds.

Difference from sycamore

In sycamore the leaves are opposite.

Difference from sweetgum

Sweetgum has a star-shaped leaf and spiky balls.

Flowering: May · Pruning: November–March

Identify by feature: Palmate leaves · Peeling bark

Looks like it, but isn’t

• Sycamore Acer pseudoplatanus: leaves are opposite. Difference from sycamore
• Sweetgum Liquidambar styraciflua: star-shaped leaf and spiky balls. Difference from sweetgum

Why grow it?

• As a pleached or roof-trained tree it gives shade and privacy on a patio without taking up much room.
• Beautiful flaking camouflage bark, attractive in winter too.
• Copes extremely well with polluted city air, paving and hard pruning.
• A strong, long-lived tree for an avenue or a park.

London plane: where does it grow best?

• Full sun.
• Almost any soil, including paved and compacted urban soil; ideally deep and not too dry.
• Shallow, dense roots: the ground beneath the tree is dry and little grows there.
• Left to grow freely, the crown becomes 20 m wide: only for a park, an avenue or a very large garden. As a pleached or roof-trained tree it also fits in a small garden.

Light

Full sun

Legal basis

Any garden soil

Moisture

Normal

Size

35 m tall, 20 m wide

Hardiness

Throughout Belgium, no protection needed

Goes well with

• Hornbeam: A low hornbeam hedge under a row of pleached trees closes off the bottom of the screen.
• Common lime: Another classic for pleached and roof-trained trees, with fragrant flowers in summer.
• Hydrangea: Flowers in the partial shade under a roof-trained tree.
• Common ivy: An evergreen ground cover that copes with the dry soil under the tree.

Good and bad companions

Goes well with

• Tolerate the shade under this tree: oregon grape, rhododendron, oleaster, japanese skimmia, garden privet, camellia, laurustinus, box-leaved honeysuckle

London plane: when and how to plant it?

1. Plant from November to March, when it isn’t freezing; pleached and roof-trained trees are sold ready-trained, root-balled.
2. Train a pleached tree on a sturdy framework of posts and wires; a roof-trained tree has a flat frame on top of the trunk.
3. Dig a generous planting hole and loosen the bottom; in a patio, leave as large an unpaved planting pit around the trunk as possible.
4. Set the tree at the same depth as before, with two stakes.
5. Water generously after planting and during dry spells in the first two summers.

Care

Watering

In dry spells during the first two years; after that it copes.

Feeding

Not needed; a pleached tree that you prune every year gets a little compost in spring.

Tying in

On pleached and roof-trained trees, tie the shoots you want to keep to the frame while they are still supple.

Fallen leaves

The large leaves break down slowly: rake them off the lawn and patio and put them on the compost heap.

Tip: Shade on a patio without a giant in the garden? Choose a ready-trained roof tree: after a few years you sit under a green roof, and every winter you cut it back.

London plane: when to prune it?

Pruning months: November–March.

When: During winter dormancy (November–March).

How:

• Tolerates hard pruning very well: suitable for pruning every year as a pleached or roof-trained tree, or for pollarding every few years into a ‘candelabra’.
• On a pleached or roof-trained tree, cut the past year’s shoots back close to the knuckle every winter, except for the branches you tie onto the frame.
• A freely growing tree needs little pruning: only remove dead, crossing and low branches.

Caution: The hairs on young leaves and the fluff from the fruit can irritate the nose, eyes and airways: wear a dust mask and safety glasses when pruning.

Pruning: when and how · Pruning calendar and basic rules

Propagation

Hardwood cuttings

In winter, push cuttings of 20–30 cm from young twigs two-thirds of their length into the ground; they root fairly easily.

London plane: how does it get through the winter?

Hardy throughout Belgium: no protection needed.

• Fully hardy.
• In winter the flaking bark is at its best, and the balls break up into fluffy seeds.

Diseases and pests

• Plane anthracnose: Brown patches along the veins, shrivelled young leaves and dying shoot tips after a cool, wet spring. The tree leafs out again; clear up the fallen leaves.
• Massaria disease: A fungus that, mainly on old trees, kills large branches from the upper side, with a risk of branch failure. Have trees over a patio, path or street checked regularly by an arborist.
• Plane lace bug: Small, lace-like bugs under the leaves, which become mottled yellow and pale. Mainly a cosmetic problem.
• Hairs and fluff: Hairs from young leaves in spring and fruit fluff in winter can irritate the nose, eyes and airways.

Through the year

• January: Winter pruning of pleached and roof-trained trees; tie shoots onto the frame.
• February: Pruning and pollarding in mild weather; planting.
• March: Last month for pruning and planting.
• April: New leaves: their hairs can irritate.
• May: Watch for anthracnose after a wet spring.
• July: Water young trees in dry spells; watch for lace bugs.
• October: Leaf fall: rake up the large leaves.
• November: Planting season starts; winter pruning can begin.
• December: Winter pruning of pleached and roof-trained trees.

What can you use it for?

Garden and landscape

The classic street and shade tree; ideal as a pleached or roof-trained tree.

Wood

Figured veneer wood (‘lacewood’).

Caution: The hairs on young leaves and the fluff from the fruit can irritate the nose and airways.

Did you know?

• Copes extremely well with polluted city air, which is why it is one of the most widely planted street trees.
• Its figured veneer wood is known as ‘lacewood’.
• In the south of France, long avenues of planes line roads and squares, planted for their shade.
• It is a hybrid between the oriental plane and the American sycamore that arose in the 17th century, probably in Spain or England.
• Along the Canal du Midi in southern France, tens of thousands of plane trees have already had to be felled because of a deadly fungal disease (Ceratocystis platani).