Viola adunca

Common Names

Hooked-Spur Violet, Early Blue Violet, Western Dog Violet, Blue Violet, Hook Violet, Sand Violet, Western Blue Violet

Summary

Hookedspur violet is a native North American perennial that grows from slender rhizomes and typically reaches about 2–16 cm in height with 1–5 erect stems. It has basal and cauline leaves that are ovate to heart-shaped, and flowers ranging from blue to violet with a white patch and purple veins at the base of the lower petals; the lower petals are white-bearded and the spur is slender and colored purple to violet or white. Fruits are short-ovoid capsules that explosively eject seeds. The species occurs across Alaska and Canada into much of the United States, occupying dry to moist meadows, coastal areas, open woods, grasslands, and disturbed ground, and tolerates coastal salt spray. Cultivation favors sun to partial shade and soils that are well-drained, moist to moderately dry, often humus-rich; hardiness is documented in USDA zones 4a–10b. Propagation is by seed (with stratification up to about 120 days) or by division; seed capsules explode for dispersal, so bagging can prevent seed loss. In landscape use, it fits native plantings, meadows, rock gardens, and woodland edges; it provides nectar for pollinators and serves as a larval host plant for butterfly species such as the Oregon silverspot and Zerene fritillary.

Lifecycle

Perennial

Height

0.5–12 inches

Spread

12-16 inches

Hardiness Zones

Zones 4-9

Sunlight Requirements

Full Sun to Partial Shade.

Soil Type

Well-drained soil, sandy to loamy textures, pH around 6–6.5

Soil Drainage

Well-drained soil

Soil pH

6.0-6.5, Prefers pH 6–6.5, Acid to neutral soil pH

Bloom Color

Blue to deep violet

Bloom Time

Spring

Foliage Color

Green

Fall Foliage Color

Green

Leaf Lifecycle

Deciduous

Growth Rate

Approximately 9 months

Seasons of Interest

Spring and Summer

Propagation Methods

Seeds, Cuttings, Division

Attracts Wildlife

Bees, butterflies, and other pollinators, hummingbirds, birds