Eryngium × zabelii ‘Big Blue’

We’ve had this one on the nursery for years, and it always draws a crowd. The main event is the electric, steel-blue flower heads, each surrounded by a spiky collar of bracts. This blue colour even extends down the stems, creating a striking silhouette from early summer right into autumn. It’s a real favourite for the bees too.

This is a clump-forming perennial with a stiff, upright habit, reaching about 60-70cm in height. It has a deep taproot, which means it’s very drought tolerant once it’s settled in, but also that it dislikes being moved. For the most intense flower colour, give it a spot in full sun and poor, well-drained, sandy soil; it won’t thank you for rich, moist conditions.

There’s very little care needed for this plant. You can cut the flower stems back after they fade, or leave the seed heads on for winter interest. It’s a tough, reliable choice for the middle of a border or a coastal garden, where it can handle the wind and salty air.