Alnus inokumae
A very fast-growing deciduous tree to 30m. Leaves are 8cm long with an oval shape, green above and downy cream below until they fall in autumn. 8cm male catkins hang in clusters in late winter, and female woody 'cones' persist on the branches through the winter.
Size
Ultimate height
Higher than 12 metresTime to ultimate height
20–50 yearsUltimate spread
Wider than 8 metresGrowing conditions
Moisture
Poorly–drainedpH
Acid, Alkaline, NeutralColour & scent
| Stem | Flower | Foliage | Fruit | |
| Spring | Cream | Green Cream | ||
|---|---|---|---|---|
| Summer | Green Cream | |||
| Autumn | Green Cream | Brown | ||
| Winter | Brown |
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 the UK
- No
- Foliage
- Deciduous
- Habit
- Columnar upright, Spreading branched
- 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
It is a nitrogen-fixer so can grow on poor soil. Suited to river banks on permanently damp soil in good light. For more information see tree cultivation.
Propagation
Propagate by hardwood cuttings or seed. For more advice see our information on how to propagate from seed (tree/shrub
Suggested planting locations and garden types
- Architectural
- Banks and slopes
Pruning
Pests
May be susceptible to alder leaf beetle, alder sucker and leaf-mining sawflies
Diseases
May be susceptible to phytophthora root rot and honey fungus
Get involved
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