Silver birch

Overview

Betula pendula is a native pioneer tree that colonises heaths and open ground, quickly growing into an airy tree with pendulous twigs, diamond-shaped leaves and white bark that cracks into black fissures with age. Lamb's-tail catkins hang from the branches in early spring, and the leaves turn butter-yellow in autumn. For smaller gardens, 'Youngii' is a dome-shaped weeping form and 'Fastigiata' is narrow and upright. Many gardeners choose the Himalayan birch, Betula utilis var. jacquemontii, whose bark is an even, chalky white.

Where to grow silver birch

Birch thrives in poor, sandy, acid soils but grows almost anywhere except waterlogged ground. Its light canopy lets spring bulbs, ferns and woodland perennials grow beneath. Keep it well away from house foundations and drains, and bear in mind that birch pollen is a common hay fever trigger.

Planting

Plant bare-root or root-balled trees in the dormant season. Small trees establish more reliably than large ones. Plant at the original depth, use a short stake on exposed sites and water generously through the first two summers.

Care through the year

Spring

Keep grass and weeds away from the base of young trees and mulch.

Summer

Young trees are shallow-rooted and suffer in drought, so water deeply in dry spells.

Autumn

Rake fallen leaves onto beds as a light mulch; they rot down quickly.

Winter

Wash green algae off Himalayan birch trunks with a soft brush and water if you want the bark at its whitest.

Pruning

Birch bleeds heavily if cut between late winter and early summer, so do any pruning when the tree is dormant in late autumn or early winter. Remove dead wood and crossing branches, and raise the crown gradually if needed.

Propagation

Collect seed from ripening catkins in late summer and sow it on the surface of a pot without covering, as it needs light to germinate. Named cultivars are grafted.

Common problems

Aphids can drip sticky honeydew onto anything below. Birch rust causes orange spots on leaves in late summer. On old or stressed trees, the bracket fungus birch polypore signals internal decay and is worth getting a tree surgeon to look at.

Guides to the problems most likely to affect silver birch:

• Drought stress
• Honey fungus

Something else wrong? Diagnose it by symptom.

Month-by-month reminders

Jobs for this plant come round in January, February, March, October, November and December. Each month page lists everything else worth doing in the garden at the same time.

Related plants

• Rowan
• Male fern
• Japanese anemone

Sources

Botanical names follow Kew's Plants of the World Online; growing attributes were checked against the references below. Text is our own. See our editorial policy.

• Kew Plants of the World Online — Betula pendula
• Wikipedia — Betula pendula