[Wikipedia] Origin, Distribution: The species is native to Western Europe from Spain and Portugal east to Germany and north to England and Wales. It is commonly grown in gardens and populations have become established in the Balkans, Australia, New Zealand, the Caucasus, Madeira, British Columbia, Ontario, Newfoundland, Nova Scotia, Oregon, Washington state, much of the eastern United States, and the Falkland Islands. (link added by Mary Ann Machi)