Great Blue Lobelia
Lobelia Siphilitica
Overview
Great Blue Lobelia (Lobelia siphilitica) is a striking perennial bestowing spires of vibrant indigo blue flowers. Ideal for adding vertical interest, this North American native thrives in USDA zones 4-9, prefers moist, well-draining soils, and partially shaded sites. It grows up to 2-3 feet tall and spreads about 1-1.5 feet wide. Blooming from late summer to early fall, it attracts butterflies and hummingbirds, enhancing garden biodiversity.

Culture
- Sun
- Full, Half
- Water
- Extra in Summer, Medium
- USDA zones
- 4–9
Shape & size
Classification
- Family
- Campanulaceae
- Climate
- Temperate
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