Siebold’s wood fern

Dryopteris sieboldii

In other languages: Dryopteris (Nederlands) · Dryopteris (Français)

Dryopteris sieboldii is a fern from East Asia, including Japan, named after the German naturalist Philipp Franz von Siebold. It hardly looks like an ordinary fern: each frond has only a few pairs of large, broad, leathery, grey-green leaflets. The plant grows about 60 cm tall and wide and gives a striking, almost tropical structure to the shade garden. It is hardy down to about −20 °C and stays green in mild winters. Plant it in shelter in humus-rich soil and give it a permanent spot.

Updated on 9 October 2026

Light
Partial shade or shade
tolerates little sun
Moisture
Normal
no wet feet
Legal basis
Sand, loam or clay
acid to neutral
Hardiness
Fully hardy
down to -20 °C
Size
0.6 m
tall, 0.6 m wide

Key facts
Pruning months	March
Height	0.6 m
Native to Belgium	No, planted
Poisonous to people and pets	Not known to be poisonous

Identify

Siebold’s wood fern: how do you recognise it?

Habit: Upright, funnel-shaped clump about 60 cm tall and wide.
Fronds: Leathery, grey-green; each frond has a few pairs of large, long, broad leaflets. Stays green in mild winters.
Spores: Ferns do not flower: the spores sit in small groups on the underside of the leaflets.
Roots: A short, sturdy rhizome with fibrous roots; the plant grows slowly.
New fronds: In spring the new fronds unroll like a crozier; they are soft and vulnerable then.

Plants: March–May and September–October · Pruning: March

In your garden

Why grow it?

A distinctive fern with large, leathery leaflets that look unlike other ferns.
Grey-green foliage that contrasts with hostas and other shade plants.
Evergreen in mild winters: interest even in the cold months.
Easy and calm: no pruning, no feeding, hardly any diseases.
A fine accent plant for under trees, the north side of a wall or a pot.

Siebold’s wood fern: where does it grow best?

Part shade to shade; in full sun the fronds scorch.
Humus-rich, moisture-retentive but free-draining soil: sand or loam, acid to neutral.
Sheltered from cold winter wind and from fierce summer sun.
Allow 50–60 cm of space per plant.

Light: Partial shade and shade
Soil type: Sand, loam or clay
Acidity: Acid or neutral
Moisture: Normal
Size: 0.6 m tall, 0.6 m wide
Hardiness: Hardy (to -20 °C)

Goes well with

Hosta: Large, soft leaves beside the tough, leathery fern foliage.
Barrenwort: A carpet of leaves and small flowers under the same trees.
Hellebore: Flowers in winter and is evergreen too.
Wood anemone: A white spring flower that fades as the fern grows in full.

Maintenance

Siebold’s wood fern: when and how to plant it?

Plant in March–May and September–October.

Plant in March–May or September–October, when the soil is neither frozen nor waterlogged.
Dig a hole twice as wide as the root ball and mix in a few spadefuls of leaf mould.
Set the plant at the same depth as in its pot, with the crown at soil level: do not bury the growing points.
Firm the soil and water in generously straight away.
Spread a layer of leaf mould around the base and keep the soil moist in the first year.

Care

Water: Keep the soil slightly moist; it does not tolerate long drought. In dry weather water generously, especially in the first year.
Feeding: A layer of leaf mould or compost in spring is enough.
Mulching: Leaf mould in autumn keeps the roots cool and moist and protects against frost.
Tidying: In March cut off damaged or brown fronds; leave healthy ones.
Position: Move it as little as possible; a quiet, permanent spot is best.

Tip: Give it a sheltered, shady spot and a layer of leaf mould: then the foliage stays nicely green in mild winters and it is ready early in spring.

Siebold’s wood fern: when to prune it?

Pruning months: March.

When: In March, before the new fronds unroll.

How:

Cut damaged and brown fronds off at the base with sharp secateurs.
Leave healthy green fronds; they protect the crown in winter.
Take care of the young, rolled-up shoots in the middle of the clump.

Pruning: when and how · Pruning calendar and basic rules

Propagation

Division: In spring, if the plant has several crowns, carefully separate them with a sharp spade and replant at once. The plant grows slowly; only divide it if necessary.
Spores: Possible but slow and a test of patience: scatter ripe spores on damp compost kept moist under a clear cover and wait for months.

Siebold’s wood fern: how does it get through the winter?

Hardy to −20 °C.

Hardy down to about −20 °C: no protection is needed in most Belgian winters.
In mild winters the fronds stay green; in hard winters they turn brown. Cut them off in March then.
In a pot: stand it against a wall and wrap the pot in hessian so the roots do not freeze.

Diseases and pests

Scorched fronds: Brown edges caused by too much sun, wind or drought. Water more and choose a sheltered, shadier spot.
Frost on new fronds: A late frost can damage the young shoots in April. Cover them with hessian or move them to shelter; they usually regrow.
Slugs: Young, soft fronds are nibbled in spring. Look for them in the evening and remove them by hand.
Wet feet: In heavy, wet soil the crown rots in winter. Plant in a well-drained spot or work in compost and a little sand.

Through the year

March: Cut off damaged fronds. Apply compost. Plant.
April: New fronds unroll. Plant. Protect young shoots from late frost.
May: Plant. Water in dry spells.
June: Water in dry spells.
July: Water in dry spells.
August: Water in dry spells.
September: Plant.
October: Plant. Mulch with leaf mould.
December: Rest. In hard frost cover the crown.

You and this species

Did you know?

The species name honours Philipp Franz von Siebold, a German physician and naturalist who worked in Japan in the 19th century and brought many Japanese plants to Europe.
The name Dryopteris comes from Greek and means ‘oak fern’, because these ferns often grow under trees.
Ferns do not form seeds but spores: they sit in small groups on the underside of the fronds.

Garden plants · All species