An evening primrose still flowering at twilight

I've not been out and about much in the last few days. This evening primrose flower surprised me,. Most of any similar flowers finished many weeks ago, and I think the unusually warmer weather has allowed more buds to form and flower.

I dole them and am always amazed at where they plants appear each year. They seem to spread around the garden at random and I've no idea what mechanism is helping them to find new sites.They ar quite happy to germinate in very tough conditions such as cracks between paving stones as well as older pot plants that have become becalmed.