Alnus alnobetula
Alnus alnobetula · Betulaceae
The gardener's calendar
In autumn, ease off feeding and take the chance to clean up around alnus alnobetula and prepare for winter.
ID card
- Foliage
- Deciduous
- Flowering
- Spring (April-May)
- Adult size
- 2 to 4 m in height
- Growth
- Moderate
- Hardiness
- -20 to -25°C
- Origin
- European Alps
- Soil type
- Well-drained, slightly acidic
Care
Exposure
Plant your Alpine alder in full sun or partial shade for optimal growth. This mountain species appreciates ventilated, bright locations, particularly in temperate climates. Avoid overly shaded areas that slow its development.
Watering
Water regularly during the first year of establishment, keeping the soil moist but not waterlogged. Once established, Alpine alder tolerates relative drought thanks to its deep root system. In very dry climates, occasional summer watering remains beneficial.
Soil and preparation
This alder prefers well-drained, slightly acidic to neutral soils, enriched with organic matter. Improve poor soil with compost at planting time. The species tolerates some winter moisture but fears prolonged waterlogging.
Pruning and training
Prune lightly after flowering to maintain a harmonious, airy shape. Remove dead or poorly oriented branches in late winter. Avoid severe pruning that distorts the naturally elegant form of the shrub.
Fertilizer
Alpine alder, like all alders, forms associations with nitrogen-fixing bacteria and enriches the soil itself. Fertilizer is rarely necessary. A mulch of compost in autumn is enough to maintain soil fertility.
Diseases and pests
This species is generally hardy and not very susceptible to diseases. Occasionally monitor for scale insects or aphids without intervention if populations remain limited. Good drainage prevents root rot, the main risk in very humid conditions.
Did you know?
The Alpine alder plays a fascinating ecological role: its roots harbour bacteria that capture atmospheric nitrogen, naturally enriching the poor soils of alpine slopes. This pioneer shrub is thus crucial for stabilizing eroded terrain and regenerating mountain flora, a true "soil engineer".
Where to buy it
Best planted in autumn so the roots settle in before summer, or in early spring once the frost has passed. Pick a plant with healthy foliage and roots that are not exposed. Best time: March, October, November.
Add this plant to my garden →Plants from the same family
- Silver birchBetula pendula
- Grey alderAlnus incana
- Dwarf birchBetula nana
- European Hop-hornbeamOstrya carpinifolia
- Turkish hazelCorylus colurna
- Italian AlderAlnus cordata
Tips generated and checked by Viridia — adapt them to your local climate.