Blueblossom
Ceanothus thyrsiflorus
Last reviewed: June 2026
Blueblossom (Ceanothus thyrsiflorus) is not on the ASPCA Animal Poison Control Center toxic plant list for dogs or cats (aspca.org, last reviewed 2026-05-21). If your pet shows symptoms after eating any plant, call the ASPCA at (888) 426-4435.
Light
full sun
Water
low
Size
72"–240" H × 72"–240" W
Bloom
Mar, Apr, May
Native to
CA, OR
Pollinators
bees, butterflies, hummingbirds
Browse plants for this ecoregion
Blueblossom is a large native shrub or small tree with glossy evergreen leaves and stunning blue flower clusters in spring. It grows quickly to 6-20 feet tall and wide, thriving in full sun with minimal water once established.
In an HOA neighborhood
Blueblossom is an HOA-friendly choice in the right placement. Maintenance level: moderate. Tidiness: 3 out of 5.
Works well in: mid zone, backyard only.
- Can grow quite large if not pruned regularly
- May appear too naturalistic/wild for formal landscapes
- Some cultivars drop blue flower petals that can stain hardscapes
Wildlife value
Host plant for pale swallowtail butterfly, California hairstreak butterfly.
Excellent pollinator plant that attracts native bees, butterflies, and hummingbirds. The dense foliage also provides nesting habitat and shelter for birds.
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 Blueblossom fit your yard? Open it in Pollinator Patch to check it against your sun, soil, and HOA-conscious filters.