Bracken

How to recognise it

Habit

Fronds stand singly or in rows along a creeping rhizome, not in a clump; 0.5–2 m tall, sometimes up to 3 m.

Frond

Triangular, two to three times divided, firm and slightly leathery; it unrolls in May like a curled crozier.

Stalk

Long, bare and sturdy; cut across at an angle near the base, it shows a dark pattern that recalls an eagle.

Spores

Under the rolled-under frond edge, from July to September; not every year and not on every plant.

Roots

Deep, black, branching rhizome that can creep for several metres.

Confusion with

Male fern and lady fern grow in a funnel-shaped clump from a single point, with short stalks. Bracken has separate, triangular fronds on long stalks.

Pruning: March, June and August

Why grow it?

• Dense stands give shelter to roe deer, birds and small mammals.
• The dead, russet fronds look lovely in autumn and winter and form a sheltering layer for insects and spiders.
• Suitable for large, natural gardens on acid soil, where few other plants will grow.
• A few specialist insects, such as certain sawflies and moths, live on bracken.
• Once a useful plant: as bedding in the stable, as packing material and burnt for potash for soap and glass.

Bracken: where does it grow best?

• In the wild in open woods, woodland edges, clearings, hedgerows and on heathland.
• Acid, dry to moist, free-draining sandy or loamy soil; it avoids lime and wet, heavy ground.
• Sun to partial shade; in deep shade it stays shorter.
• In the garden: only in a large, natural garden or woodland edge where it may spread, with a root barrier.

Goes well with

• Sessile oak: The light crown of an oak suits a woodland edge on acid soil.
• Silver birch: Light shade on the same acid sand.
• Heather: For a transition from woodland edge to heath; do keep the bracken in check.
• Foxglove: Purple flower spikes in clearings on acid soil.
• Honeysuckle: Climbs into the trees above and smells sweet in summer.

Bracken: when and how to plant it?

1. Think twice: in a small garden it overruns everything, and it is poisonous. Choose a fern that grows in a clump instead, such as male fern.
2. Buy a plant from a nursery or take a piece of rhizome from a garden where it has to go; never dig it up in a nature reserve.
3. First put a root barrier all round, as deep as possible and ideally 60 cm or more, or plant it in a large sunken tub.
4. Plant in March–April, 5–10 cm deep, in acid, loose soil.
5. Water in dry spells in the first year; after that, no more.

Care

Watering

Not needed after the first year.

Feeding

Not needed.

Spreading

Mow or cut young fronds outside the area you want, in June and again in August; after a few years the rhizome is exhausted.

Old fronds

Leave the brown fronds over winter as protection; remove them in March if the layer is too thick.

Gloves

Wear gloves: the stalks are tough and the frond edges can cut.

Tip: To make it retreat, cut it twice a summer, in June and August: a single cut is not enough to exhaust the rhizome.

Pruning and mowing

Pruning months: March, June and August.

When: To keep it in check, in June and August; old fronds possibly in March.

How:

• Cut or mow young fronds at ground level, ideally twice a summer: this exhausts the rhizome.
• Bending or bruising the stalks also works and is used in nature reserves.
• Remove the cuttings; they rot down slowly.
• In March, remove dead fronds where the layer is too thick; elsewhere leave some for insects.

Caution: Wear gloves and long sleeves, and preferably cut before the spores ripen.

Pruning: when and how · Pruning calendar and basic rules

Propagation

Rhizome

The main method: the rhizome creeps further underground. In March you can cut off a piece with a bud and plant it elsewhere.

Spores

It also spreads by spores, but young plants from spores are rarely seen in the wild.

Bracken: how does it get through the winter?

Hardy to −25 °C.

• The fronds die at the first night frost and turn russet brown.
• The dead fronds remain standing or lying as a brown layer: shelter for insects, mice and birds.
• The rhizome overwinters deep in the soil and is fully hardy; young fronds are, however, sensitive to late frost.

Diseases and pests

• Spreading: It takes over large areas. Cutting twice a summer and a root barrier help.
• Poisonous to animals: Horses, cattle and sheep that eat it fall ill. Keep it out of pastures and hay.
• Late frost: Young, unrolling fronds freeze in May. The plant sprouts again.
• Crowding out heather: On heathland it overgrows heather. Cut young fronds in good time.

Through the year

• March: Remove old fronds where needed. Plant.
• April: Plant.
• May: Young fronds unroll like curls.
• June: Cut young fronds where it is not wanted.
• July: Fronds fully grown. Spores form.
• August: Second cut where it spreads too far.
• October: The fronds turn russet brown.
• November: Leave the brown fronds for wildlife.

Did you know?

• The species name aquilinum means ‘of the eagle’: in a stalk cut at an angle you see a figure that recalls an eagle with spread wings.
• Bracken grows on every continent except Antarctica and is one of the most widespread plants in the world.
• In the past, large amounts of bracken were burnt to make potash, a raw material for soap and glass.