It is native to Eurasia and North Africa, but it can be found throughout much of the temperate world as a common roadside weed.

Each flower has a tubular calyx of fused sepals lined with ten green or purple-red veins.

In the British Isles it mostly occurs near the coast of England, Wales, Scotland and Ireland, but also sporadically inland.

It is found in sandy or gravelly, often acidic, soils in arable fields, on wasteland and on walls, as well as poor dry pastures on the coast, and on sand dunes in the Channel Islands.

[4] This plant has been in long-term decline, especially in the more northern parts of Europe, and is no longer present in many inland sites in Britain and Ireland, with a population reduction of 80% in the last ten years reported in 2006.