Red Alder
Alnus rubra
Last reviewed: June 2026
Light
part sun
Water
high
Size
240"–800" H × 180"–480" W
Bloom
Mar, Apr, May
Native to
CA, ID, MT, OR and 1 more states
Pollinators
bees, moths
Browse plants for this ecoregion
Red alder is a fast-growing deciduous tree that can reach 20-65 feet tall. It thrives in moist conditions and produces catkins in spring, with serrated green leaves that turn yellow in fall. This nitrogen-fixing tree naturally improves soil quality but requires consistent moisture to establish well.
In an HOA neighborhood
Red Alder takes more care to keep looking intentional in a front yard. Maintenance level: high. Consider it for backyard or mid-zone beds rather than the street edge.
Works well in: backyard only.
- Extremely large mature size inappropriate for most residential lots
- High water requirements may conflict with xeriscape preferences
- Fast growth can appear uncontrolled without regular pruning
Wildlife value
Host plant for white-lined sphinx moth.
Supports bees and moths during its spring bloom period with abundant catkins. The tree also provides nesting habitat for birds and its seeds feed various wildlife species.
Native range data from the USDA PLANTS Database and regional native plant society lists. Pollinator and host plant associations compiled from GBIF, iNaturalist, and published ecological literature.
Does Red Alder fit your yard? Open it in Pollinator Patch to check it against your sun, soil, and HOA-conscious filters.