Great Blue Lobelia
Lobelia siphilitica (Great Blue Lobelia)
Lobelia siphilitica, commonly known as Great Blue Lobelia, is a moisture-loving, late-summer perennial known for its tall spikes of bright blue flowers. Ideal for rain gardens, pond edges, and naturalized landscapes, it adds bold color, vertical interest, and pollinator-friendly beauty to moist, sunny areas.
Distinctive Features
This native perennial features strong, upright stems topped with dense spikes of deep blue, tubular flowers. Blooming from late summer into early fall, the flowers provide essential nectar for bees, butterflies, and hummingbirds. The lush green foliage creates a strong contrast to the vivid blooms, while its upright form adds height and structure to garden spaces.
Growing Conditions
- Sun Exposure: Full sun to partial shade.
 - Soil: Prefers moist, rich, well-drained soil.
 - Water: Requires consistently moist soil; thrives in wet conditions.
 - USDA Hardiness Zones: 4-9.
 
Ideal Uses
- Rain Gardens: Thrives in areas with consistent moisture.
 - Pond Edges: Adds bright color and vertical interest to water features.
 - Naturalized Areas: Ideal for creating bold, natural landscapes.
 - Pollinator Gardens: Attracts hummingbirds, bees, and butterflies.
 
Low Maintenance Care
- Watering: Requires consistent moisture, especially in hot weather.
 - Pruning: Deadhead spent flowers to encourage additional blooming.
 - Fertilizing: Apply compost or a balanced fertilizer in spring.
 - Winter Care: Mulch to protect roots in colder climates.
 
Why Choose Lobelia siphilitica?
- Bold Blue Blooms: Adds striking late-summer color to moist landscapes.
 - Pollinator-Friendly: Attracts hummingbirds, bees, and butterflies.
 - Moisture-Loving: Ideal for rain gardens and pond edges.
 - Low Maintenance: Easy to care for with minimal upkeep.
 
For bold color, vertical interest, and pollinator-friendly beauty, Lobelia siphilitica is an excellent choice for rain gardens, pond edges, and naturalized plantings.
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