Oenothera macrocarpa 'Dwarf Silver'
Common Name: dwarf evening primrose
Type: Herbaceous perennial
Family: Onagraceae
Zone: 4 to 8
Height: 0.25 to 0.50 feet
Spread: 1.00 to 1.50 feet
Bloom Time: May to August
Bloom Description: Yellow
Sun: Full sun
Water: Dry to medium
Maintenance: Low
Flower: Showy
Leaf: Colorful
Tolerate: Drought, Clay Soil, Dry Soil, Shallow-Rocky Soil

Culture

Easily grown in average, dry to medium, well-drained soil in full sun. Tolerates poor and/or limy soils, drought and some light shade. Easily grown from seed and will self-seed under optimum growing conditions.

Noteworthy Characteristics

Oenothera macrocarpa, commonly called Missouri evening primrose, is a sprawling, Missouri native plant which occurs on limestone glades and bluffs and rocky prairies in the Ozark region south of the Missouri River. Typically grows 6-12" tall and features very large (3-5" across), solitary, 4-petaled, mildly fragrant, bright yellow flowers which open for only one day (usually open late afternoon and remain open until the following morning). Flowers arise from leaf axils and are generally upward-facing, but sometimes rest on or touch the ground. Long spring to summer bloom period. Flowers are followed by somewhat unique, winged seed pods (2-3" long). Narrow, lance-shaped leaves. This species was formerly called (and is still often listed for sale as) Oenothera missouriensis.

Genus name is unclear but may have come from the Greek words oinos and theras meaning wine-seeker in probable reference to an ancient use of the roots of genus plants in scenting wine.

Specific epithet means large-fruited.

'Dwarf Silver' was discovered growing in a bed of typical Oenothera macrocarpa plants and many years later, in 2015, was introduced by High Country Gardens. It is a semi-dwarf that grows 5 to 6 in. tall and 14 to 16 in. wide, approximately half the usual size of a Missouri evening primrose. It has small, narrow, lance-shaped silvery leaves and large, 4-petaled bright yellow flowers.

Problems

No serious insect or disease problems. Root rot may occur in wet, poorly drained soils.

Garden Uses

Best in border fronts or rock gardens. Also effective in wild gardens, meadows, cottage gardens or native plant gardens. A showy plant which can be grown in poor, dryish soils.