Eryngium amethystinum Sea Holly features multitudes of open umbels of prickly steel-blue flowers, which are a favourite of bees and other pollinating insects and for cut flowers, fresh or dried. This is a very hardy species, small flowered but with superb colour in the garden, especially nice contrasting with yellow or gold neighbours. Compact in size, growing to only 45 cm or so, this may be useful towards the border edge. Plants spread to form a shrubby tangle of attractive foliage and flowers. Tolerant of hot, dry sites, and soils high in salts. For drying, pick stems just as the flower clusters open fully, and hang upside down to dry in a warm, dark place. Attractive to butterflies.
Very easy to grow in even in poor soils. Prefers a well drained and sunny position.