The leaves are edible raw or cooked: They are used in soups, stews etc., and as a flavouring in potato salad etc. The aromatic leaves are used as a tea substitute [S. Cornucopia - A Source Book of Edible Plants. Kampong Publications 1990]

http://www.pfaf.org, https://pfaf.org/User/Plant.aspx?LatinName=Achillea+ageratum

Two Achillea species—A. millefolium and A. ageratum—are described in an 18th-century Polish medical help book entitled Compendium medicum auctum as natural remedies, also for skin disorders

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8018854/ Drobnik J., Bacler B. Medicinal plants in an 18th-century Polish medical guide compendium medicum auctum. Part 2. Annales Academiae Medicae Silesiensis. 2009;63:51–65. [Google Scholar] [Ref list]