Mature plants are absolutely stunning plants! Large plants 2-3 m (6-9 ft) tall withvery ornamental silky white plumes appear in late summer. This native of Argentina isa tender perennial that is reliably hardy in Zone 6b and up. In Zones 5 and colder, it will have to be potted up and brought indoors in order to survive the winter. The seed is very slow to germinate and it can take 3 to 4 years for the plant to reach its full size.