Yellow Evening Primrose

Oenothera flava

Also known as: Murdock's Evening Primrose

Native to:
Canada, Mexico, United States

📍 View on iNaturalist →

Taxonomy

Division:
Magnoliophyta | - Flowering plants
Family:
Onagraceae
Genus:
Oenothera
Species:
Oenothera flava
USDA Symbol:
OEFL

Growth Characteristics

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

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)
Pollen Specialist Bee Keystone:
★★★☆☆ Native pollen specialist bee species supported by this genus (NWF)

Garden & Ecology Notes

Wildlife Value:
bees, butterflies

Soil Requirements

Soil Type:
sandy, well-drained, nutrient-poor soil
pH:
6.0 - 8.0 (slightly acidic to neutral)
Drainage:
excellent drainage required
Moisture:
dry to moderate
Notes:
native to arid and semi-arid regions

Propagation & Germination

Stratification:
Cold/moist stratification required — 30–60 days
Germination Time:
14–30 days
Notes:
Seeds germinate readily after cold stratification; sow on soil surface and keep moist.

Pre-treatment: Seeds are imbibed in water for 4 hours and undergo a 90 day cold, moist stratification at 1 to 3°C in the refrigerator.

Establishment: Seeds are hand collected in August when capsules begin to split open. Seeds are brown at maturity. They are collected in paper bags and kept in a well ventilated drying shed prior to cleaning.

Source: npn.rngr.net

ORGHPS Germination Guide: Sow @ 20C. Germinates within 3 months.

Source: Ontario Rock Garden & Hardy Plant Society