| Color Oklahoma Please click on a photo below to view a larger image. |
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Photo by Clarence A. Rechenthin @ USDA-NRCS Plants Database
The Missouri Primrose is more often called the big-fruit evening primrose (Oenothera macrocarpa). This perennial member of the Onagraceae produces large, lemon-yellow flowers with four petals. It can grow to be about 1 foot in height but more often spreads across the ground. The fruits of this plant are large and are shaped like a four pointed star. This plant thrives in rocky soils and is most often found in the central and western counties of Oklahoma.