Oenothera Species, Common Evening Primrose, Hoary Evening Primrose, Night Willow-Herb
Oenotherabiennis

Category
Biennials

Water Requirements
Drought-tolerant; suitable for xeriscaping
Average Water Needs; Water regularly; do not overwater

Sun Exposure
Full Sun

Foliage
Herbaceous
Succulent

Foliage Color

Height
36-48 in. (90-120 cm)
4-6 ft. (1.2-1.8 m)
6-8 ft. (1.8-2.4 m)

Spacing
6-9 in. (15-22 cm)
9-12 in. (22-30 cm)

Hardiness
USDA Zone 5a: to -28.8 °C (-20 °F)
USDA Zone 5b: to -26.1 °C (-15 °F)
USDA Zone 6a: to -23.3 °C (-10 °F)
USDA Zone 6b: to -20.5 °C (-5 °F)
USDA Zone 7a: to -17.7 °C (0 °F)
USDA Zone 7b: to -14.9 °C (5 °F)
USDA Zone 8a: to -12.2 °C (10 °F)
USDA Zone 8b: to -9.4 °C (15 °F)

Where to Grow

Danger
N/A

Bloom Color
Bright Yellow

Bloom Characteristics
Flowers are fragrant

Bloom Size

Bloom Time
Mid Summer
Late Summer/Early Fall

Other details
May be a noxious weed or invasive

Soil pH requirements
6.1 to 6.5 (mildly acidic)
6.6 to 7.5 (neutral)
7.6 to 7.8 (mildly alkaline)

Patent Information
Non-patented

Propagation Methods
From seed; sow indoors before last frost
From seed; direct sow after last frost

Seed Collecting
Collect seedhead/pod when flowers fade; allow to dry
Properly cleaned, seed can be successfully stored