It is native to South America, especially Argentina, but it is known on several other continents where it is an introduced species, and in some areas such as eastern Australia, a noxious weed.

[1][2] This is a clumpy perennial herb growing branching, hairy stems to about half a meter in maximum height.

It has abundant foliage of oblong wavy-edged green leaves four to nine centimeters long.

The curving terminal spike inflorescences hold several tiny bright purple flowers with rounded lobes and tubular yellow throats.

Biological pest control is being investigated for reducing the spread of this plant in New South Wales and surrounding areas in Australia.