[9] The genus Lobelia comprises a substantial number of large and small annual, perennial and shrubby species, hardy and tender, from a variety of habitats, in a range of colours.

[10] The genus Lobelia was first formally described in 1753 by Carl Linnaeus in Species plantarum and was named after the Flemish botanist Matthias de Lobel (1538–1616).

[11][12][13] Lobelia is probably the base form from which many other lobelioid genera are derived; it is therefore highly paraphyletic and not a good genus in a cladistic sense.

[14] A New Zealand study concluded that local species of Hypsela, Isotoma and Pratia should be treated as Lobelia.

The cultivars 'Kompliment Scharlach'[17] and 'Pink Elephant'[18] have gained the Royal Horticultural Society's Award of Garden Merit.

[23] Herbalist Samuel Thomson popularized medicinal use of lobelia in the United States in the early 19th century.

[24] Because of lobeline's similarity to nicotine, the internal use of lobelia may be dangerous to susceptible populations, including children, pregnant women,[25] and individuals with cardiac disease.