This salt-loving plant presumably originated in northern Europe. It has now spread along the margins of main roads in the countryside, where the splashes of salt-rich spray from winter gritting saturate roadside soil.
It forms a low and narrow band which starts at the very edge of the road, a few inches wide. Best seen in spring when it is in flower. These pictures taken on April 23rd, by the A513 outside Shugborough Park, but the plant seemed to be flowering on all the local A-roads outside built up areas.