Katsura tree

Katsura tree: how do you recognise it?

Habit

Tree of 10–20 m, often multi-stemmed, with a broad crown.

Leaf

Opposite, 5–10 cm, round to heart-shaped with a scalloped edge and palmate veins; young leaves reddish.

Bark

Greyish-brown, peeling in strips on older trees; often multi-stemmed.

Flower

Inconspicuous reddish flowers before the leaves; male and female flowers grow on separate trees.

Fruit

Small, pod-like fruits in clusters, on female trees only.

Difference from Judas tree

The Judas tree has alternate, untoothed leaves and pink flowers on the branches.

Difference from small-leaved lime

Small-leaved lime has alternate, lopsided heart-shaped leaves with a pointed tip.

Flowering: March–April · Pruning: July–August and November–February

Identify by feature: Heart-shaped leaves · Opposite leaves · Pods

Looks like it, but isn’t

• Judas tree Cercis siliquastrum: alternate, untoothed leaves and pink flowers on the branches. Difference from Judas tree
• Small-leaved lime Tilia cordata: alternate, lopsided heart-shaped leaves with a pointed tip. Difference from small-leaved lime

Why grow it?

• One of the finest autumn colours, with a scent of caramel as the leaves fall.
• Elegant, round leaves that emerge reddish; often a graceful, multi-stemmed tree.
• Little pruning needed: it grows into a fine shape on its own.
• Grows in sun and partial shade.

Katsura tree: where does it grow best?

• Sun or partial shade. The autumn colour is best in sun, but then the soil must stay moist.
• Moist, fertile, well-drained soil, acid or chalky. On dry soil its leaves droop or drop in summer.
• Sheltered from cold winds and late frosts, which can damage the young leaves.
• Allow for a crown about 8 m across and 15 m or more tall: a tree for a large garden or a park. For a smaller garden there is the weeping form ‘Pendulum’.

Light

Sun or partial shade

Legal basis

Any garden soil

Moisture

Moist to wet

Size

15 m tall, 8 m wide

Hardiness

Throughout Belgium, no protection needed

Goes well with

• Japanese maple: Another Asian tree with fine autumn colours, for the same moist, sheltered spot.
• Witch hazel: Fragrant in winter and yellow to orange in autumn: together a garden with something to enjoy in every season.
• Hydrangea: Also likes moist soil and partial shade, and flowers in summer, when the katsura only has leaves.

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

Katsura tree: when and how to plant it?

1. Plant from October to March, in frost-free weather, root-balled or container-grown.
2. Mix compost or leaf mould into the planting soil: it holds moisture.
3. Choose a spot where the soil doesn’t dry out in summer, so not right against a wall or under large trees that take up all the water.
4. Mulch with leaf mould or wood chips after planting.
5. Water during dry spells for the first few years: that is the most important care.

Care

Watering

Regularly in dry spells for the first few years, and later too during long dry periods: drooping or falling leaves in summer are a distress signal.

Mulch

A layer of leaf mould or wood chips keeps the soil cool and moist.

Feeding

A little compost in spring; nothing more is needed.

Autumn leaves

Leave the fallen leaves under the tree: they enrich the soil, and it is the fallen leaves that smell of caramel.

Tip: Plant the katsura along a path or near the patio: that way you’ll smell the caramel scent of the fallen leaves in autumn.

Katsura tree: when to prune it?

Pruning months: July–August and November–February.

When: Dead, diseased and broken branches can be removed at any time of year. If pruning is needed, do it in winter (November–February) or in summer (July–August).

How:

• It grows into a fine shape on its own, often multi-stemmed: let it keep its natural form.
• Want a single trunk? Then only remove double leaders on a young tree. On a multi-stemmed tree, keep three to five well-spaced stems.
• Don’t saw off thick branches: large wounds heal slowly.

Caution: Needs moist soil and won’t tolerate long dry spells: water it for the first few years.

Pruning: when and how · Pruning calendar and basic rules

Propagation

Sowing

In autumn, collect the fruits of a female tree with a male tree nearby, let them split open and sow the fine, winged seeds in a tray in spring, barely covered. Keep them moist.

Katsura tree: how does it get through the winter?

Hardy throughout Belgium: no protection needed.

• Fully hardy.
• A late frost in April can scorch the young, reddish leaves; the tree then grows back.
• In winter you can admire the graceful shape of a multi-stemmed tree and the peeling bark of older trees.

Diseases and pests

• Drought: Drooping, withering or early falling leaves in summer. Water generously and mulch; on dry soil it is in the wrong place.
• Late frost: Brown, shrivelled young leaves in spring. Harmless for a healthy tree: it grows back. Plant it in a sheltered spot.
• Leaf scorch: Brown leaf margins in full sun during hot, dry summers. A spot with some afternoon shade and moist soil helps.

Through the year

• January: Formative pruning of a young tree, in frost-free weather.
• February: Finish formative pruning; plant root-balled or container-grown trees.
• April: The leaves emerge reddish; watch out for late frost.
• July: Water during dry spells; summer pruning and removal of dead branches.
• August: Water during dry spells; finish summer pruning.
• October: Autumn colour and the caramel scent of fallen leaves.
• November: Leave the leaves as mulch; plant; formative pruning can start again.
• December: Formative pruning in frost-free weather.

What can you use it for?

Garden and landscape

Ornamental tree with one of the finest autumn colours, and a scent of caramel as the leaves fall.

Wood

Used in Japan for furniture and for go and shogi boards.

Did you know?

• The fallen autumn leaves smell of burnt sugar: in German the tree is called ‘Kuchenbaum’, cake tree.
• The scent comes from maltol, a substance also found in caramel and baked bread.
• In Japan the wood is used for furniture and for go and shogi boards.
• The scientific name Cercidiphyllum means ‘with leaves like a Cercis’: the leaves resemble those of the Judas tree.
• The caramel scent of the autumn leaves comes from maltol, a substance also found in burnt sugar and baked bread.
• The scientific name Cercidiphyllum means ‘with leaves like the Judas tree (Cercis)’.