Western Blue Virginsbower

Clematis occidentalis

Native to:
Canada, United States

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Taxonomy

Division:
Magnoliophyta | - Flowering plants
Family:
Ranunculaceae
Genus:
Clematis
Species:
Clematis occidentalis
USDA Symbol:
CLOC2

Growth Characteristics

Life Cycle:
Perennial
Growth Habit:
Vine
Height:
300 cm
Light Requirements:
Part Shade,Shade
Drought Tolerance:
Medium
Bloom Months:
may,jun,jul
Bloom Colors:
blue, purple, violet

Wildlife Benefits

Bees:
★☆☆☆☆ Documented bee visitation (GBIF)
Butterflies & Moths:
★☆☆☆☆ Documented Lepidoptera association (GBIF)

Keystone Species Ranking

Caterpillar Keystone:
★★☆☆☆ Butterfly & moth species supported by this genus (NWF)

Garden & Ecology Notes

Wildlife Value:
bees, butterflies, birds
Deer Resistant:
Yes

Soil Requirements

Soil Type:
rich, well-drained loamy soil
pH:
5.5 - 7.0 (slightly acidic to neutral)
Drainage:
excellent drainage required
Moisture:
dry to moderate
Notes:
prefers rocky or wooded slopes

Propagation & Germination

Stratification:
Cold/moist stratification required — 60–90 days
Germination Time:
30–180 days
Notes:
Germination can be slow and erratic. Seeds may require light for optimal germination.

The above propagation data sourced from Claude AI

Pre-treatment: Cold-moist stratification for 30 days at 1–5°C (34–41°F).; then Cold-moist stratification for 60 days.

Source: Claude AI

ORGHPS Germination Guide: Repeated cycles of 20C then 4C, 3 months each. Very prolonged. Tails on pulsatilla/clematis: leaving on has no effect.

Source: Ontario Rock Garden & Hardy Plant Society