Lobelia siphilitica is a flowering herb from the Campanulaceae family of plants. It is more commonly known as the Great Blue Lobelia or the Blue Cardinal flower, and is found across eastern sections of the United States and Canada. It is a perennial plant, meaning it blooms each year, and flowers relatively late in the season. Historically, the herb had a number of uses as a natural remedy for many different ailments, including colds and nosebleeds.
This herb provides late summer color, flowering anywhere from late July to early October. While the lobelia siphilitica is a perennial plant, its flowering capacity only lasts a few years. Blue and purple spiked flowers appear in vertical patterns along the herb and attract the insects required for pollination. The blue colored blooms are particularly attractive to hummingbirds. Flowers are split into two separate lips, with the upper lips protruding further than the lower lips.
The average Great Blue Lobelia grows to approximately 3 feet (1 m) and spreads to just 1 foot (30 cm). It prefers quite moist to wet soil with adequate drainage and nutrition. The ideal location for the lobelia siphilitica is a partly shady or full sun location. If planted in appropriate soil with adequate light access, the herb is a low maintenance plant that requires only occasional pruning and watering. The plant is typically unable to pollinate itself and relies on insects, such as bees, to perform this task, but it can occasionally self-seed if the perfect environment exists.
Originating from Missouri, the lobelia siphilitica is most commonly found in wetland areas, swamps, lowland forests and wooded areas, and along the edges of streams. These plants are not often afflicted by an excessive amount of insects or damaging diseases. In a number of states, however, the herb is considered endangered or vulnerable due to competition for resources and the eradication of its natural environment. These states include New York, Massachusetts and Maine.
One of the origins of this herb's name results from its historical use as a treatment for certain types of sexually transmitted diseases. The plant was also used by a number of Native American tribes as a natural cough remedy and as a means to stop recurrent nosebleeds. Some groups even believed that if a man and a woman consumed the herb, they would be guarded against the evils of divorce. The most common use for lobelia siphiltica is as a cold and headache remedy.