About

Alnus serrulata is a deciduous shrub that often grows in a multi-stemmed form, capable of creating dense thickets. Its leaves are thick and green, lacking any notable autumn coloration and remaining on the plant until they turn green before dropping. In winter, the upright catkins develop a deep red hue, adding visual interest. The small female flowers mature into clusters that form durable wooden cones.

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, Partial shade
Soil type
Chalk, Clay, Loam, Sand
Soil pH
Acid, Alkaline, Neutral
Soil moisture
Moist but well-drained, Poorly-drained
Aspect
East-facing, North-facing, South-facing, West-facing
Exposure
Exposed, Sheltered
UK hardiness
H5

Plant details

Plant type
Shrubs
Habit
Bushy, Suckering
Foliage
Deciduous
Height
4-8 metres
Spread
4-8 metres
Time to full height
5-10 years
Suggested uses
Wildlife gardens

Care notes

Cultivation
Needs good light, permanently damp soil but very little fertility as they have nitrogen-fixing nodules on their roots. They are used for river bank stabilisation and other land reclamation purposes. This is seen to be much more tolerant of drought than other alder species
Pruning
Pruning group 1
Propagation
Grow from seed or hardwood cuttings
Pest resistance
May be susceptible to alder sucker and leaf-mining sawflies
Disease resistance
May be susceptible to Phytophthora and honey fungus