Lupinus rivularis

Common Names

Riverbank Lupine, Streambank Lupine, Riverside Lupine, Stream Lupine, Nine Finger

Summary

Lupinus rivularis, Riverbank Lupine, is a native western North American perennial herb reaching 1–5 feet tall with a deep taproot, growing in coastal habitats and streambanks west of the Cascades, it has palmately compound leaves with 5–9 leaflets and racemes of showy light purple to blue flowers, sometimes with white shading, and it emits a distinct aroma that attracts pollinators, sources note cultivation and uses: prefers sunny to full-sun positions with well-drained sandy or gravelly soils, tolerates seaside salt conditions, hardy in USDA zones 5–9, propagated by seed with scarification or hot-water soaking to overcome dormancy, with germination in about two weeks, forms a nitrogen-fixing pioneer that provides erosion control and soil enrichment, supports pollinators, and serves in restoration, ground-cover, and ornamental plantings

Lifecycle

Annual, Biennial, Perennial

Height

1-5 feet

Spread

2-3 feet

Hardiness Zones

Zones 4a-9b

Sunlight Requirements

Ideally full sun, tolerates partial sun and partial shade.

Soil Type

Well-drained sandy or gravelly soil

Soil Drainage

Well-drained soil (preferably deep, sandy or gravelly).

Soil pH

Neutral to slightly acidic, tolerates a wide range of soil pH

Bloom Color

Purple to blue-lavender

Bloom Time

Spring and Summer

Foliage Color

Green

Fall Foliage Color

Green

Leaf Lifecycle

Deciduous

Growth Rate

Fast-growing

Seasons of Interest

Spring and Summer

Propagation Methods

Seeds

Attracts Wildlife

Attracts bees, butterflies, birds