As the name suggests the evening primrose, family Onagraceae, flowers during the evening and throughout the night. The flowers are supposed to last until noon. These particular flowers in my garden look just like evening primrose, but they flower all day and all night. Unless someone can tell me otherwise I shall assume that they are indeed evening primrose, but perhaps a variety that flowers all blooming day!
They are American natives that were introduced to the UK in the 1600s. They are also known as “Sundrop” or “Evening Star”. I believe that all of the plant is edible, but the roots were particularly favoured as a meal. Native Americans also used the leaves to make tea. The seeds are a source of Gamma-Linolenic Acid and the oil from the seeds is used in many herbal preparations.
They are an important food source for moths which feed on the nectar, pollinating the plant in return. During the day the same relationship is courted with bumblebees and other bees.
The pollen is large and connected by stringy viscin threads, made from sap. These web-like pollen clumps can be seen hanging off the legs of bees as they fly off from the flower. You can see what the pollen looks like under an electron microscope here.
Not only is this big blousy plant attractive to look at, beautifully scented and good for attracting pollinators such as bees and moths, but you can also eat it. There are a couple of recipe ideas here.