A fine genus of plants, grown for their spiky foliage and bracts, silvery blue, silvery green or just plain silver, with teasel-like heads of flowers, the shape and size of an egg, although in the same is a quail’s egg, and in other a duck’s. The plants include the sea hollies, and some spectacular ones with vicious spines. Many are monocarpic, but are easily propagated from seeds, and may seed themselves gently in the garden.