About Papaver cambricum L.
Papaver cambricum L. has pinnately divided leaves made up of further pinnately divided leaflets. Mature plants reach a height of 30 to 60 cm (12 to 24 inches). It blooms from May through July. Its flowers are distinctly yellow or orange, with four petals. The green sepals are coarsely hairy and drop off soon after the flower opens. It produces numerous small black seeds in summer, held in a long, ribbed capsule that opens via flaps, and spreads easily from these seeds. This species is endemic to upland regions of Western Europe; its native range includes the mountains of the Iberian Peninsula, the Pyrenees, the Massif Central, and western parts of the British Isles (Wales, south-western England, and parts of Ireland). It has been widely naturalised outside of its native range. Papaver cambricum grows in damp, shady locations on rocky ground. In its westernmost native locations, it is increasingly found on more open ground with less vegetation cover. It is particularly well adapted to colonising gaps and crevices between rocks and stones. This growth habit allows it to spread into urban environments, where it grows between paving slabs and along the edges of walls.