Caucasian Alder (Alnus subcordata)

Caucasian Alder

Alnus subcordata

Its glossy leaves and pendulous catkins bring quiet woodland charm. Deciduous tree; common name: Caucasian Alder.

Full sun
1–2/week
Moderate
🌱

Plant Needs

☀️
Sunlight Full sun to partial shade; tolerant of dappled woodland conditions and open riparian habitats
💧
Watering Water deeply during prolonged dry spells; highly tolerant of moist, even waterlogged soils
🌡️
Temperature Hardy to -15°C; adapts well to temperate climates, avoids extreme summer heat above 32°C
🔍

Characteristics

  • Leaf: Glossy dark green, subcordate (heart-shaped) base, serrated margins, 6–12 cm long
  • Flower: Male catkins are long and pendulous; female catkins are small, oval, and woody when mature
  • Stem/Bark: Smooth gray-brown bark when young, becoming fissured with age
🛠️

Care Guide

Watering

Keep soil consistently moist during active growth periods

Fertilization

Light application of balanced organic feed in early spring. Nitrogen-fixing root nodules reduce need for frequent fertilization

Crushed eggshell powder:Crush clean, dried eggshells into fine powder; sprinkle lightly around the base to improve soil structure and add calcium
Pruning
  • Remove dead or damaged branches in late winter before new growth emerges
  • Thin crowded inner branches to improve airflow and light penetration
  • Avoid heavy pruning; maintain the tree's natural upright shape
⚠️

Toxicity

Warning: this plant may be toxic.

Pets & Humans

Pets: ASPCA: Non-toxic to cats

Humans: No known toxic effects to humans

📖

Garden Uses & Culture

Culture: N/A

Usage: Soil stabilization for riparian zones, ornamental shade tree, nitrogen fixation to improve soil fertility