Rocky Mountain Willowherb

Epilobium saximontanum

Native to:
Canada, United States

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Taxonomy

Division:
Magnoliophyta | - Flowering plants
Family:
Onagraceae
Genus:
Epilobium
Species:
Epilobium saximontanum
USDA Symbol:
EPSA

Growth Characteristics

Life Cycle:
Perennial
Growth Habit:
Forb/herb
Height:
60 cm
Light Requirements:
Full Sun
Drought Tolerance:
Low
Bloom Months:
jun,jul,aug,sep
Bloom Colors:
pink, white

Wildlife Benefits

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

Garden & Ecology Notes

Wildlife Value:
bees, butterflies
Fire Ecology:
Fire adapted — tolerates or benefits from fire
Fire Notes:
Colonizes disturbed and burned areas; not dependent on fire but benefits from post-fire open conditions.

Soil Requirements

Soil Type:
rocky, well-drained, nutrient-poor soil
pH:
5.5 - 7.0 (slightly acidic to neutral)
Drainage:
excellent drainage required
Moisture:
dry to moderate
Notes:
often found in mountainous regions

Propagation & Germination

Stratification:
Cold/moist stratification required — 30–60 days
Germination Time:
14–30 days
Notes:
Seeds require light for germination; surface sow and keep moist.

The above propagation data sourced from Claude AI