The Medicinal Plant Garden

of Birmingham-Southern College

  • Lobelia cardinalis and siphilitica
  • Lobelia cardinalis and siphilitica
  • Lobelia cardinalis and siphilitica

Common Name

Cardinal Flower (L. cardinalis) and Great Blue Lobelia (L. siphilitica)

Related Species

L. splendens, L. fulgens (USDA)

Geographic Distribution and Habitat

Found across eastern North America and the southwest portion of the United States (USDA). This plant tends to grow in ditches, swamps, ravines, and stream banks, due to its need for wet or moist soil. Lobelia may also be found in open pastures, savannahs, and the edges of woodlands. Though the plant requires wet or moist soil, it can grow in many light conditions and has low water requirements (Wildflower Database).


Lobelia is a perennial dicot in the Campanulaceae family (USDA). The plant can grow to be between 1 to 6 feet tall and has 8-inch long red or blue, tubular flowers that bloom from May to October (Wildflower Database). Hummingbirds and butterflies are common pollinators for the cardinal flower because they can easily reach into the tube-shaped flowers (Wildflower Database).

Portion of the Plant Used

Traditionally, the leaves, roots, and flower blossoms of Lobelia have been used for folk medicine (Hamel and Chiltoskey, 1975).

Traditional Uses

Cherokee Indians used Lobelia for headache relief by crushing the plant and using a cloth to apply it to the pained area (Hamel and Chiltoskey, 1975). A similar application method was used to apply crushed root to sores (Hamel and Chiltoskey, 1975). They would also make an infusion with the root to treat digestive problems, typhoid, rheumatism, and worms (Hamel and Chiltoskey, 1975). Infusions made from the leaves of the plant were used to treat colds and fevers (Hamel and Chiltoskey, 1975). The Cherokee also used the plant to treat syphilis (Hamel and Chiltoskey, 1975). The Iroquois used Lobelia, often in conjunction with other plants, to reduce pain and treat epilepsy (Herrick, 1977). The flower blossoms and roots were used as a treatment for cramps (Herrick, 1977). The Iroquois would also use the whole plant as a treatment for overcoming grief (Herrick, 1977).


There does not seem to be any medically-related research on L. cardinalis and L. siphilitica in the peer-reviewed literature. The alkaloid lobeline, from the related species L. inflata L., is an agonist and antagonist at nicotinic cholinergic receptors and inhibitor of vesicular monoamine uptake, has been widely studied and has been investigated for it use for nicotine and amphetamine addiction (see reviews by Dwoskin et al., 2002; Marlow and Stoller, 2003; Elksheft et al., 2008; Crooks et al., 2011).