Lobelia siphilitica, commonly known as great blue lobelia, is a clump-forming perennial with upright, lance-shaped green leaves forming dense, architectural foliage. In late summer it produces spikes of vivid blue to violet-blue flowers, creating a striking display along pond margins and in wet soils.
This species is valuable for pollinators, particularly bees and butterflies, and contributes to wetland biodiversity. Its upright, clump-forming habit and preference for consistently moist or shallowly submerged soil make it ideal for pond edges, bog gardens, and naturalistic water features.
