Calylophus serrulatus (Plains Evening Primrose)

Calylophus serrulatus (Plains Evening Primrose) is a low, shrubby, woody-based perennial boasting small, yellow, four-petaled, stalkless flowers borne from the upper leaf axils. Blooming from mid-spring to mid-summer, the blossoms are more profuse at the beginning of the flowering period, becoming sporadic throughout the rest of the summer.

Calylophus serrulatus (Plains Evening Primrose) is a low, shrubby, woody-based perennial boasting small, yellow, four-petaled, stalkless flowers borne from the upper leaf axils. Blooming from mid-spring to mid-summer, the blossoms are more profuse at the beginning of the flowering period, becoming sporadic throughout the rest of the summer. Unlike many other evening primrose species, the flowers open in the evening and remain open for the entire day. They are followed by 1 in. long seed capsules (2.5 cm). The 2 in. leaves (5 cm) are narrow, lance-shaped, and sharply toothed. Native to western North America, Calylophus serrulatus can be found growing in dry prairies and mesas. A valuable plant for dry border fronts, rock gardens, and prairies.

  • Grows up to 6-18 in. tall and wide (15-45 cm).
  • Best in full sun in gravelly or sandy, dry, well-drained soils. Excellent drought tolerance.
  • A great choice for prairies and meadows, wildflower gardens, rock gardens, and border fronts.
  • No serious pest or disease issues.
  • Propagate by seed or cuttings taken in early summer. This is a taprooted plant that can be difficult to transplant once established.
  • Native to western North America.

Requirements

Hardiness 3
– 8

Climate Zones 1, 1A, 1B, 2, 2A, 2B, 3, 3A, 3B, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 18, 19, 20, 21, 22, 23, 24
Plant Type Perennials
Plant Family Oenothera – Primroses – Sundrops
Exposure Full Sun
Season of Interest Spring (Mid,Late)Summer (Early,Mid)
Height 6"
– 2'
(15cm
– 60cm)
Spread 6"
– 2'
(15cm
– 60cm)
Spacing 6″
– 18″
(15cm
– 45cm)
Water Needs Low
Maintenance Low
Soil Type Loam, Sand
Soil pH Acid, Alkaline, Neutral
Soil Drainage Well-Drained
Characteristics Showy
Native Plants United States, Midwest, Illinois, Indiana, Iowa, Kansas, Michigan, Minnesota, Missouri, Nebraska, North Dakota, South Dakota, Wisconsin, Rocky Mountains, Colorado, Montana, Wyoming, Southeast, Arkansas, Kentucky, Southwest, Arizona, New Mexico, Oklahoma, Texas
Tolerance Drought, Dry Soil, Rocky Soil
Garden Uses Beds and Borders
Garden Styles Gravel and Rock Garden, Informal and Cottage, Prairie and Meadow