Seeds of Eryngium giganteum 'Miss Willmott's Ghost' - Giant Sea Holly.

Eryngium giganteum 'Miss Willmott's Ghost', also known as Giant Sea Holly, is a large thistle, typically biennial, that forms clumps of vibrant green heart-shaped foliage that turns silver in summer. It displays large clusters of steel blue or soft green conical heads, surrounded by beautifully serrated and silver bracts, very spiny. This plant often dies after flowering, but self-seeds spontaneously in light soil. Perfect in wildflower beds, in fresh or dried bouquets, of great ornamental value, it enjoys sun and well-drained, deep, even dry, rocky and poor soils.

Giant Sea Holly is a plant of the Apiaceae family (Umbelliferae), native to the Caucasus and Iran. Hardy down to -20°C, this blue thistle develops a rosette of deciduous, basal, heart-shaped leaves, medium green with white veins, which turn more greyish with heat. In July, bluish-grey inflorescences at maturity form conical and spiny cylinders 10cm (3.9in) long, accompanied by cut, leathery, silver bracts also 10cm (3.9in) long, all on stiff and branched stems. The dried flowers hold up well in dried bouquets. This short-lived perennial plant, often semelparous, readily self-seeds in rocky and deep soils.

Eryngium giganteum is well suited for rock gardens, flower beds or wild gardens, alongside Dianthus, Perovskia, and Stipa. This plant is beautiful everywhere, without overshadowing other blooms. Its rapid growth is a blessing for brand new gardens, or to fill the spaces left empty by a harsh winter. The semi-open cut flowers are splendid in dried bouquets, and make wonderful table decorations for Christmas.