Coneflower – Echinacea purpurea – Your garden Herb that promotes immune system health.
Echinacea is genus of herbaceous flowering plants in the daisy family. There are nine species commonly called purple coneflowers. They are perennials and very drought tolerant.
Purple coneflower is reputed to be immunostimulator, being effective in promoting immune system health and warding off infections and also some people use it as laxative.
Echinacea angustifolia was widely used by the North American Plains Indians for its general medicinal qualities. Echinacea was one of the basic antimicrobial herbs of eclectic medicine from the mid 19th century through the early 20th century, and its use was documented for snakebite, anthrax, and for relief of pain. In the 1930s echinacea became popular in both Europe and America as a herbal medicine. 
Echinacea Tincture Recipe: http://www.ehow.com/way_5529325_echinacea-tincture-recipe.html
How to Harvest Echinacea for Tea: http://www.ehow.com/how_8356584_harvest-echinacea-tea.html
Tincture: A tincture is an alcoholic extract (e.g. of leaves or other plant material) or solution of a non-volatile substance (e.g. of iodine, mercurochrome).