This is a genus of plants known as evening primroses, which reflects that the flowers open in the evening, and then fade away the next morning, and that they are pale yellow. However, they are not all yellow - some of them are pink or white. And the fact that individual flowers fade is not at all bad, as new ones emerge each day, for an astonishing long period. The unfurling of an flower is well worth watching. It only takes a few minutes, and the movement of the petals is clearly visible.

Oenothera macrocarpa is a very fine evening primrose, with very large pale yellow flowers. With such large flowers, the opening is very obvious, and can be initiated by gently touching the petals, so there is a novel way to entertain guests.