Purple showy heads of composite flowers on the ends of long stems.
Experimental studies show that extracts of echinacea have significant immune system stimulating activity. It may reduce the duration and severity of cold and flu symptoms. It works by enhancing the particle digestion capacity of white blood cells, which then increases their ability to attack foreign particles, such as cold and flu viruses.
''Echinacea purpurea'' is a species of flowering plant in the genus ''Echinacea'' of the family Asteraceae. Its cone-shaped flowering heads are usually, but not always, purple in the wild. It is native to eastern North America and present to some extent in the wild in much of the eastern, southeastern and midwest United States.