About
Alnus incana is a conical tree that can reach heights of up to 20 meters. Its dark green leaves can grow to 10 centimeters in length, featuring a grey-white, hairy underside. In late winter or early spring, before the foliage emerges, the tree produces yellow-brown male catkins that hang in clusters of three or four. The ovoid fruit appears during the summer months.
About the genus
Alnus comprises robust deciduous trees and sizable shrubs characterized by their rounded foliage and, during winter, noticeable catkins.
Growing conditions
- Sunlight
- Full sun
- Soil type
- Chalk, Clay, Loam, Sand
- Soil pH
- Acid, Alkaline, Neutral
- Soil moisture
- Moist but well-drained, Poorly-drained, Well-drained
- Aspect
- North-facing, West-facing, East-facing, South-facing
- Exposure
- Exposed, Sheltered
- UK hardiness
- H7
Plant details
- Plant type
- Trees
- Habit
- Columnar upright
- Foliage
- Deciduous
- Height
- Higher than 12 metres
- Spread
- wider than 8 metres
- Time to full height
- 20-50 years
- Suggested uses
- Coastal, Cottage and informal garden, Wildlife gardens
- Native to
- Europe, Caucasus
Care notes
- Cultivation
- Grow in moderately fertile, moist but well-drained soil in full sun or part shade. Noted for its ability to thrive in poor, wet conditions but is also tolerant of dry soils
- Pruning
- Pruning group 1 between leaf fall and midwinter
- Propagation
- Propagate by seed or hardwood cuttings
- Pest resistance
- May be susceptible to alder sucker, alder leaf beetle and leaf-mining sawflies
- Disease resistance
- May be susceptible to Phytophthora and honey fungus