Oenothera macrocarpa (Evening Primrose)

Oenothera macrocarpa                                                                                                    (formerly O. missouriensis)(Evening Primrose) If bright yellow is wanted for the front of the border, this perennial is ideal. Canary-yellow, mildly fragrant blooms atop dark-green lanceolate leaves that form a basal rosette and spiral up the flowering stems. 9-12", Z3-8.

Photo: Growing Colors