Blue eryngo

Eryngium planum, the blue eryngo or flat sea holly, is an erect perennial herb in the Apiaceae native to dry grasslands, steppes and rocky open ground from central and eastern Europe across to Central Asia, and widely grown as an ornamental and cut flower. Plants form a basal rosette of long-petiolate, ovate to oblong, leathery, glossy dark-green leaves 5 to 15 centimetres long with crenate-serrate margins; in their second and subsequent years they send up rigid, much-branched, ridged stems 30 to 90 centimetres tall that become suffused with a striking metallic steel-blue colour in their upper portion. The smaller stem leaves are sessile, palmately three to five lobed and spiny-margined. Tiny pale blue to violet flowers are densely packed into ovoid to cylindrical heads 1 to 2 centimetres long, each subtended by a star-like involucre of six to eight narrowly lanceolate, sharply spinose, blue-tinted bracts that give the inflorescences their thistle-like appearance. The fruit is a small ovoid schizocarp covered with whitish scales.