A species of Eurasia, introduced and, in part, escaped from cultivation in North America. Except for a 1901 collection by O. A. Farwell from Detroit (Wayne Co.), all Michigan specimens have been gathered since 1935, most often in lawns, gardens, and along roadsides, including saline habitats; but also along streams and doubtless in other disturbed sites.

The corolla is usually a striking brick-red. Besides the characters given in the key, hairy filaments and leaves ± gland-dotted (especially beneath) will help to identify this distinctive species. Blue and white forms occur; the white is not known from Michigan, though the blue form has been found rarely in SE Michigan (and in adjacent Essex Co. Ontario.)