Alnus × spaethii
A large, fast-growing tree with a conical habit, to a height of over 12m, with large, long and serrated green leaves that are flushed purple when young. One of its main features is the display of yellow catkins in spring. An ideal specimen for a large space or for a street
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Size
Ultimate height
Higher than 12 metresTime to ultimate height
20–50 yearsUltimate spread
4–8 metresGrowing conditions
Moisture
Moist but well–drained, Poorly–drained, Well–drainedpH
Acid, Alkaline, NeutralColour & scent
| Stem | Flower | Foliage | Fruit | |
| Spring | Brown Yellow | Green Purple | ||
|---|---|---|---|---|
| Summer | Green | Brown | ||
| Autumn | Green Purple Red | |||
| Winter | Brown Yellow |
Position
- Full sun
Aspect
East–facing or North–facing or South–facing or West–facing
Exposure
Exposed or Sheltered Hardiness
H7Botanical details
- Family
- Betulaceae
- Native to GB / Ireland
- No
- Foliage
- Deciduous
- Habit
- Columnar upright
- Genus
Alnus are vigorous deciduous trees and large shrubs with rounded leaves and often conspicuous catkins in winter
- Name status
Correct
How to grow
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
Propagation
Propagate by seed or hardwood cuttings
Suggested planting locations and garden types
- Coastal
- Wildlife gardens
- Low Maintenance
Pruning
Pruning group 1 between leaf fall and midwinter
Pests
May be susceptible to alder sucker, alder leaf beetle and leaf-mining sawflies
Diseases
May be susceptible to Phytophthora and honey fungus
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