It is native to
Italy, but it can be found growing wild as an
introduced species in parts of western North America, including
California, western
Washington, and
British Columbia, It occurs naturally in moist, moderately nutrient-rich places. In Britain it is regarded as something of a weed, spreading readily on stony waste ground and walls, although it is tolerated for its attractive, long-lasting flowers which are very attractive to bees. ==Toxicity and chemistry==