This bright blue firework of a flower is an eryngium (or sea holly) – a fabulous architectural plant. There are many different eryngiums mostly grown ornamentally and can be annual or perennial (this one is perennial), usually blue or white (the most well-known being ‘Miss Willmott’s Ghost’). The flowers are in the dome in the centre and the blue spikey bits are basal bracts…and painful.

Like: free-draining soil (dry in winter), full sun – it grows well in our clay soil where I’ve planted it beside a building (tends to be drier here), it does get full sun but no special attention over winter

Great for: flower arrangements (fresh or dried), architectural interest in winter, pollinators

Looks good with: roses, in gravel gardens, in perennial ‘natural’ gardens

Historically used in various parts of the world for food (E. foetidum – vegetable and herb) and medicine (E. campestre – lowers blood sugar; E. creticum – for scorpion stings; anti-inflammatory).