It forms an incredibly tight, symmetrical, nearly round rosette resembling a massive artichoke. It grows roughly 30 to 60 cm (1 to 2 feet) tall and 60 to 120 cm (2 to 4 feet) wide. Its rigid, broad leaves are a striking steely powder-blue or silvery-gray color and come armed with dark reddish-brown to black teeth. They are finished with a stout, sharp terminal spine up to 3.5 cm long.
