Grey Alder
Alnus incana
Last reviewed: June 2026
Grey Alder (Alnus incana) is a deciduous tree native to northern and western US states, blooming February through March. This moisture-loving species attracts bees, beetles, and moths while tolerating various light conditions.
The USDA PLANTS Database (opens in new tab) does not flag Grey Alder as toxic to livestock.
Light
part shade
Water
high
Size
180"–600" H × 180"–360" W
Bloom
Feb, Mar
Native to
AZ, CA, CO, CT and 27 more states
Pollinators
bees, beetles, moths
Browse plants for this ecoregion
Grey alder is a fast-growing deciduous tree that thrives in moist conditions and partial shade. It produces distinctive catkins in late winter to early spring and develops into a medium to large tree with attractive grey-green bark.
Growing Grey Alder
Grow Grey Alder in part shade and high water. Mature plants reach 180 to 600 inches tall and spread 180 to 360 inches wide. Expect moderate maintenance to keep it looking intentional in a front yard.
In an HOA neighborhood
Grey Alder takes more care to keep looking intentional in a front yard. Maintenance level: moderate. Consider it for backyard or mid-zone beds rather than the street edge.
Works well in: backyard only.
- Grows very large (15-50 feet)
- Requires consistently high water which may conflict with xeriscape preferences
- Fast growth can appear uncontrolled
Wildlife value
The early spring catkins provide crucial nectar for bees, beetles, and moths when few other food sources are available. The tree also supports various bird species and provides habitat for wildlife.
Common questions
- When does Grey Alder bloom?
- Grey Alder blooms in February and March, producing catkins before the leaves emerge.
- What pollinators visit Grey Alder?
- Grey Alder attracts bees, beetles, and moths. The wind-pollinated catkins also provide early season pollen for various beneficial insects.
- Where is Grey Alder native in the United States?
- Grey Alder is native to 31 US states, primarily in northern regions from Maine to Washington and extending south through mountain states like Colorado and New Mexico.
- What growing conditions does Grey Alder prefer?
- Grey Alder thrives in high moisture conditions and tolerates full sun to partial shade. It naturally grows along streams, wetlands, and other moist sites.
- Is Grey Alder toxic to livestock?
- The USDA PLANTS Database does not flag Grey Alder as toxic to livestock.
- Is Grey Alder HOA-friendly?
- Grey Alder takes more care to look intentional in a front yard. Consider it for backyard or mid-zone beds rather than the street edge.
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 Grey Alder fit your yard? Open it in Pollinator Patch to check it against your sun, soil, and HOA-conscious filters.