Tim Fitzharris / Evening Primrose (Oenothera erythrosepala) and Prairie Verbena, North America

Tom Vezo / Evening Primrose (Oenothera sp) flowers in desert, Joshua Tree National Park, California

Tom Vezo / Evening Primrose (Oenothera sp) flowers in desert, Joshua Tree National Park, California

Tim Fitzharris / Drummond's Phlox (Phlox drummondii) and Evening Primrose (Oenothera sp) near Leming, Texas

MYN / Niall Benvie / Large flowered Evening primrose (Oenothera glazioviana) in flower, Dundee, Scotland, August. meetyourneighbours.net project

Niall Benvie / Large flowered Evening primroses (Oenothera sp) in flower against white background sheet, about to be photographed in outdoor studio set up in the field, Dundee, Scotland

Tim Fitzharris / Evening Primrose (Oenothera erythrosepala) with Grizzly Bear Cactus (Opuntia erinacea), North America

Tim Fitzharris / Butterfly feeding on nectar in a field of Indian Blanket (Gaillardia pulchella) and Evening Primrose (Oenothera hookeri) flowers, Texas

Tom Vezo / Evening Primrose (Oenothera sp) flowers in desert, Joshua Tree National Park, California