Cotton Thistle are large, architectural plants, which have spiny leaves, often covered with a layer of downy silver or white hairs. They also produce large thistle flower heads in either white or purple.
There are about 60 species, mostly biennial, which are native to Europe, especially the Mediterranean, and western Asia. They grow in dry, open areas of wasteland and mountain regions. They seed freely and in parts of Australia and North America, they have become naturalised and are now considered to be an invasive weed.
They require full sun and fertile, but free-draining soil. They are ideal for gravel areas or wildlife gardens.