Most of the Amaranthus species are summer annual weeds, grown in South America.
 An example of a crop weed that is grown in gardens is the corncockle, (Agrostemma githago), which was a common weed in European wheat fields, but is now sometimes grown as a garden plant
==== Americas ====In Brazil, green amaranth was, and to a degree still is, often considered an invasive species as all other species of amaranth (except the generally imported A

