About

Alnus x spaethii is a robust, rapidly growing tree that typically reaches heights exceeding 12 meters. It has a conical shape and produces large, elongated leaves with serrated edges, which exhibit a purplish tint during their early development. In spring, the tree showcases clusters of yellow catkins. This species is well-suited for expansive areas or urban streetscapes.

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
East-facing, North-facing, South-facing, West-facing
Exposure
Exposed, Sheltered
UK hardiness
H7

Plant details

Plant type
Trees
Habit
Columnar upright
Foliage
Deciduous
Height
Higher than 12 metres
Spread
4-8 metres
Time to full height
20-50 years
Suggested uses
Coastal, Wildlife gardens

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 once established
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