Rudbeckia hirta, the common wildflower which is also known as the black-eyed Susan, has been used for medicinal purposes for hundreds of years. Certain Native American tribes used the flower in the 1800s for medicinal treatments. The Cherokee, for example, used the cheerful-looking flower to ease urinary tract infections and earaches as well as for gynecological issues. Rudbeckia hirta also was used traditionally by the Cherokee for back pain and swelling, and they mixed it with other flowers such as fairywand and hepatica. Some other tribes, including the Iroquois and the Seminole, used Rudbeckia hirta for the treatment of snakebites and wounds. Other common uses include the treatment of worms, fever, diarrhea, earaches and headaches.
The black-eyed Susan is related to the purple coneflower, also known as Echinacea. The purple coneflower has its own medicinal uses, including boosting the immune system, which is why it is often taken to help ward off colds. Rudbeckia hirta has a similar immune-boosting power. Like Rudbeckia hirta, Echinacea was at one time used for snakebites by Native Americans. When Echinacea could not be found, they used Rudbeckia hirta in its place.
Black-eyed Susans are not picky about where they grow, popping up along roadsides and other open spaces, and they are easy to care for. The plant’s commonness has not detracted from its use in the modern garden. The showy daisy-like flowers, which grow on thin stems from a base clump of leaves, is often used in butterfly, wildflower and perennial gardens, and when grown in large numbers provides a stunning view. It is particularly attractive when showcased against nearby purple or white coneflowers, and peach or black hollyhocks.
The black-eyed Susan is sometimes also called yellow ox-eye daisy or brown-eyed Susan. The flower is a main ingredient in some homemade yellow dyes, a tradition that was begunby Potawatomi Indians. The Potawatomi used the dye to color woven items, such as mats, and they combined the golden flowers with other flowering plants, such as the rush, to create different shades. Handlers should take care to ensure they are not allergic because the black-eyed Susan has been known to irritate the skin. The plant also is reportedly toxic for some animals, including sheep and cattle.