Mertensia platyphylla

Common Names

Broadleaf Bluebells, Western Bluebells, Broadleaf Bluebell

Summary

Mertensia platyphylla, now recognized as Mertensia subcordata and commonly known as Western bluebells or broadleaf bluebells, is a deciduous perennial herb in the Boraginaceae. It reaches about 12–36 inches tall and spreads laterally by rhizomes. Native to the Pacific Northwest, specifically western Washington and Oregon west of the Cascades to the Coast Mountains, it favors moist, shady spots such as streambanks, damp woods, and woodland edges. In spring it bears clusters of bluish-purple, bell-shaped flowers on tall stems, set against broad, oval leaves that emerge bright green and deepen as the season progresses; the foliage dies back after flowering.

In cultivation, it prefers full shade and moist soil, thriving in dappled sunlight or light shade, and may require supplemental water if grown in drier areas. Bees (including bumblebees) and butterflies (such as swallowtails and fritillaries) are attracted to the plant, and its seeds feed small birds; it also serves as a host and larval food source for several native butterflies and moths and offers cover for ground-dwelling insects and small mammals. It makes a good groundcover and is deer resistant, with landscape uses in woodland gardens, shady raingardens, and erosion control.

Lifecycle

Perennial

Height

1.5-3 feet

Spread

1.5-5 feet

Sunlight Requirements

Ideally full shade.

Soil Type

Moist, well-drained soil

Soil Drainage

Well-drained, moist soil.

Bloom Color

Blue

Bloom Time

Spring to Summer

Foliage Color

Fresh, bright green foliage that darkens to a rich deep green as the season progresses.

Fall Foliage Color

Rich, deep green

Leaf Lifecycle

Deciduous, Other

Growth Rate

Fast

Seasons of Interest

Spring, Summer, and Fall

Attracts Wildlife

Sources indicate bees (especially bumblebees) and butterflies are attracted, hummingbirds are attracted, seeds provide a food source for small birds such as juncos and sparrows in late summer/fall, and it serves as a host/larval food source for several native butterflies and moths