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Great Blue Lobelia - Lobelia siphilitica




Blue Cardinal Flower, Lobelia siphilitica, also known as Great Lobelia, is a native perennial that is found in moist to wet locations along streams, springs, swamps and low wooded habitats. This clump-forming flower has dainty light to dark blue, tubular, 2-lipped blooms that sit atop unbranched, leafy stalks that typically reach 2 – 3′ tall and spread 1 – 1.5′. Though tolerating full sun in more northern climates, siphilitica prefers partial shade and needs constant moisture, making it well-suited for rain gardens or environs with rich, humusy, medium to wet soils. Lobelia are a favorite of bees, butterflies and hummingbirds, and produce a secondary compound known as “Iobeline,” which deters herbivores such as deer.


Photo: Emerson Sapienza 


Great Blue Lobelia - Lobelia siphilitica

  • Zone: 4-9

    Spread: 1-1.5 ft.

    Height: 2-3 ft.

    Sun: Full sun to partial shade

    Water: Average to wet

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