General poisoning notes for Lobelia siphilitica

Blue cardinalflower (Lobelia siphilitica) is a native herb found along wet river banks in southern Ontario. This plant contains an alkaloid, lobeline, that caused poisoning when the extract was used as a home remedy. For more information, see the notes under Indian- tobacco ( Lobelia inflata).

Hardiness Zones: 3 to 10

Height: 3 ft Spread: 2 ft

Type: herbaceous perennial

Flowers: Blue

Comments: Great Blue Lobelia is native to North America and produces spikes of blue flowers in late summer. The plant grows well in moist to wet soils and so is useful near water. The plant may be short-lived but will tend to reseed.

Propagation: Seed or division.

Lobelia siphilitica . . GREAT BLUE LOBELIA

1 to 3 ft. . . Sun to mod. shade . . Avg. to wet soil . . Native . . Tall dense spikes of blue flowers in late summer. Thick foliage, often branching. Very showy. Culture is similar to Cardinal Flower. . . Great Blue Lobelia was a popular cure for syphilis in N. America and Europe until proven ineffective. . . . . Zones 5 to 9

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