This is a very tough, evergreen rhizomatous subshrub (ht 75 cm) from Europe, Northern Turkey, North Africa and the Azores, which forms a wide clump. Sometimes known as the insect plant, it has tiny flowers in the middle of its spiky 'leaves' (actually stems), looking for all the world like little bugs. Another colloquial name for the plant is butcher's broom, because apparently in days gone by, the mature spiky branches were bundled and used as brooms by butchers to clean their chopping blocks! It forms an impressive mass, and will grow in difficult spots where few other plants will thrive: from dry shade with root competition from big trees to places in full hot sun! It will grow in any soil as long as it isn't actually waterlogged. It can also grow well in a pot in the garden, on a shady verandah or even indoors.
If there are male and female plants, showy red berries will form from the flowers - although there is apparently at least one self-fruiting form. It is reasonably frost hardy. Propagation is by dividing the rhizomes.