Spiraea douglasii – Hardhack, Spirea

At a Glance:

  • Family: Rosaceae
  • Plant Type: deciduous, thicket-forming dense shrub
  • Distribution: Mostly Pacific Coast, California to Alaska
  • Habitat: wetlands and lake margins, light shade to full sun
  • Height: 2-7 feet tall
  • Flowers/Fruits: cone shaped cluster of pink-purple flowers. Dry brown seeds stay attached to stem through winter.
  • Flowering Season: June-August
  • Leaves: oblong/elliptical and 1-3 inches long. The lower half margin (edge) is smooth (entire) and the tip of the leaf is toothed. Color is green with a lighter green underside. The underside is also wooly/hairy.
  • Generation: Perennial
  • Notable feature: besides the cone shaped magenta blooms, this rose creates a very dense thicket. One of its common names is “hardhack” because it’s not an easy chore to hack through these plants to make a path.

Restoration and Conservation

Spirea is a vigorous native plant prized in restoration applications. It grows and spreads very quickly and competes well against reed canarygrass and Himalayan blackberry. Once established, it can slow water flow down and stabilize soil, preventing erosion and creating habitat for animals. Hummingbirds and pollinators use the nectar that the flowers produce. Small birds use the thickets for shelter and nesting, and eat the seeds that stay on the stems throughout winter.

References and Resources

This article was written by Sarah Verlinde. For questions regarding the UWB/CC Plant Tour, contact Sarah at severlin@uw.edu.