Earth Day at Washington Park Arboretum
Annual Earth Day celebration combining hands-on conservation volunteering with public education — set among 230 acres of spring bloom, including Pacific dogwood and the famous Azalea Way.
About the event
The Arboretum Foundation hosts this annual Earth Day event at Washington Park Arboretum, one of Seattle's most important urban green spaces. The 230-acre arboretum — managed jointly by the University of Washington Botanic Gardens and the City of Seattle — holds one of the Pacific Northwest's finest living collections of trees and shrubs, and late April is its peak season.
Each year's event is organized around a different ecological theme. The 2025 theme was "Powerful Pollinators," with programming centered on bee hotels, native plant gardens, and the arboretum's "no mow meadow" zones that support birds and beneficial insects. The event typically runs 9 a.m.–1 p.m. on the Saturday nearest April 22.
What to expect
Visitors can join a guided volunteer work crew removing invasive plants from arboretum collections (pre-registration required, ages 15+), build a pollinator hotel to take home, visit the UW Botanic Gardens discovery cart for hands-on activities, and speak with Master Gardeners about creating pollinator-friendly home gardens.
The arboretum itself is reason enough to visit in late April — Azalea Way is typically approaching peak bloom, the cherry collection is often still showing color, and Pacific dogwood trees flower throughout the forest collections. The event is just one more reason to be there.