Lobelia (lobelia inflata)

The genus Lobelia, named for the 16th-century Flemish botanist Matthias de L’Obel, contains more than 400 species. Native to eastern North America, Lobelia inflata was well known to the Cherokee, Iroquois, and other Native Americans, who used the powerful plant to treat a variety of conditions.

Samuel Thomson, an American herbalist-physician of the early 19th century, recommended lobelia as a muscle relaxant during childbirth; as a poultice for healing abscesses; and for the treatment of epilepsy, tetanus, diphtheria, dysentery, and whooping cough. Many herbalists of the time believed that the vomiting induced by lobelia cleansed the patient.

The herb’s powerful and toxic effects on the central nervous system have caused it to fall from favor in recent times. Lobelia is not an herb for home experimentation — confine it to the “history” portion of your garden, and keep it far away from children. All parts of the plant contain toxins; ingesting it can be fatal.


Plant profile

Common Names: Lobelia, Gag Root, Indian Tobacco, Puke Weed, Vomit Root

Description: Branched stems, up to 3 feet tall; loose spikes of violet-blue blooms; inflated seedpods; lanceolate, toothed, alternate leaves. Stems exude milky latex juice when broken

Hardiness: Annual or biennial; to Zone 2

Family: Campanulaceae

Flowering: Midsummer to fall

Parts Used: Leaves

Range/Habitat: Native to eastern North America and eastern Siberia; open fields and woods

Medicinal use

Native Americans smoked lobelia leaves to relieve asthma and bronchitis (hence the common name Indian tobacco). The herb contains a muscle-relaxing alkaloid called lobeline, which is related to nicotine. By relaxing the muscles of the smaller bronchial tubes, lobeline opens airways, stimulates breathing, and promotes the loosening of phlegm. It has also been used to induce vomiting in people who have been poisoned. The plant is highly toxic, however, and should never be used internally for its traditional purposes. Some herbalists still use it externally to relieve muscle tension and to soothe bruises and bites.

Caution: Even a miniscule amount of this herb, alone or in an herbal preparation, can cause paralysis, coma, and death.

How to grow it

An attractive garden border plant, lobelia thrives in well-drained, fertile soil and full sun to partial shade. Sow the seeds in moist soil, either directly in your garden in spring or in seed flats indoors in late winter. The seeds need light for germination; do not cover them with soil. Space plants 8 to 12 inches apart, and water during dry spells. Propagate by gathering seed in fall.