Red alder
Red alder
Alnus rubra
tree☀️ full-sun🪴 moist-loam📏 medium🌡️ RHS H7
📋Quick Facts
Height
15.0-25.0m
Spread
8.0-12.0m
About
Fast-growing nitrogen fixer ideal for wet soils and pioneer plantings.
Top tip
Red alder is a nitrogen fixer for wet sites; coppice or thin as other trees establish around it.
Also known as: Olsza czerwona, Aliso rojo, Roterle, Amieiro-vermelho, Red alder, Rode els, Ontano rosso, Aulne rouge
Pest Resilience
4/5 — Good resilience
Few pest problems; alder flea beetle occasionally but damage is minor.
The red alder year in your garden
Dispatching imaginary bots to check your garden out...
What to do now
How to Propagate
🌰Seed
Easy✂️Cutting
ModerateHardiness Zones
H1a (tender)H7 (very hardy)
RHS H7
USDA 4–5 equivalent