Common Name: Missouri Evening-primrose
Scientific Name: Oenothera macrocarpa
Family: Evening Primrose
Height: 8 - 12 inches
Bloom Period: May, June
Description: Stems are spreading or ascending. Leaves are elliptic and can be up to 5 inches long. White, tightly-pressed hairs on the surface give them a silvery appearance. Flowers are composed of four, large, yellow petals with a conspicuous, four-lobed, X-shaped stigma.
Comments: The name macrocarpa, meaning, “large fruit,” refers to the showy, 3-inch long seed pods. The pods turn golden and shiny, with four wide wings that give pods a squared appearance when viewed on end. The flowers open in the evening and wither by noon of the following day. The flowers are pollinated at night by sphinx moths. Missouri Evening-primrose is found on shallow, rocky soil on prairies and bare roadside cuts in the eastern three-quarters of the state.