About

Alnus cordata subsp. neapolitana is a rapidly growing deciduous tree, reaching heights of approximately 15 meters when provided with optimal conditions. It features heart-shaped leaves that are dark green and glossy on the upper surface, with branches exhibiting a horizontal growth habit. The foliage persists into autumn, maintaining its green coloration for an extended period. In spring, both male and female trees produce yellow catkins, which are followed by clusters of greenish-brown fruits resembling pineapples. During winter, small, winged seeds are released. This tree serves effectively as a windbreak and can be used as a screen in expansive landscapes.

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
Soil pH
Acid, Alkaline, Neutral
Soil moisture
Moist but well-drained, Poorly-drained
Aspect
East-facing, South-facing, West-facing
Exposure
Exposed, Sheltered
UK hardiness
H6

Plant details

Plant type
Trees
Habit
Spreading branched
Foliage
Deciduous
Height
Higher than 12 metres
Spread
4-8 metres
Time to full height
20-50 years
Suggested uses
Architectural
Native to
S Italy

Care notes

Cultivation
Thrives in fertile, moist but well-drained soil, but tolerates a range of conditions including poor drainage. Can make a fast-growing screen on wet sites
Pruning
Pruning group 1
Propagation
Propagate by seed or by hardwood cuttings
Pest resistance
May be susceptible to alder sucker, alder leaf beetle and leaf-mining sawflies
Disease resistance
May be susceptible to phytophthora root rots and honey fungus