Stevia rebaudiana is an herb that is closely related to sunflowers. Because stevia is indigenous to South America this plant has been used by Paraguoy Indians of South America for thousands of years. They used it as a sweetener, and as a tonic for stomach ailments. It can be found in the wild as far north as Arizona and Texas.
It is widely recognized for its sweet leaves. These leaves contain a substance known as steviosides which ranges anywhere from 30 times to 300 times sweeter (when concentrated) than sugar.