Sea holly

Botanical name: Eryngium

These architectural, spiny, almost sculptural perennials, some looking superficially like thistles, can make a dramatic statement in a summer border. Let them rise above low-growing plants, or mingle them among roses and taller perennials to provide a contrast in form and texture.


Upright, branching stems bear greenish-white or blue flowers gathered into a cone surrounded by a ruff of spiny bracts. In some, the upper part of the plant is suffused with metallic blue.


Most like very free-draining soil, some even thriving in poor, dry soil, in sun.


Very fertile, overly rich soils are unsuitable, as is a position in shade.

Did you know?

The flowers are long-lasting and can be cut and dried for use in winter arrangements.

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