Lobelia siphilitica 'Alba' is a striking white flowered cultivar of the native Great Blue Lobelia offering vertical interest and late season blooms that illuminate moist to wet shady gardens. Its tubular flowers rise on upright spikes and are particularly effective at attracting long tongued pollinators. With its tidy clumping habit and adaptable nature it is an excellent choice for naturalistic plantings, rain gardens, and woodland edges.
Height & Spread: 24 - 36 in x 12 - 18 in
Bloom Time: Late summer to early fall
Light Requirements: Full sun to part shade
Soil Preference: Moist to wet, humus rich soil
Watering Needs: High; thrives in consistently moist areas
Deer Resistance: Rarely browsed by deer due to bitter latex
Native Status
While 'Alba' is a cultivated variety, its parent species Lobelia siphilitica is native to much of eastern and central North America. It retains the same ecological value and suitability for restoration and wildlife plantings.
WILDLIFE & INSECTS
Bees
- Highly attractive to bumblebees and long tongued native bees such as Bombus fervidus and Bombus impatiens which can access its deep floral tubes.
Butterflies
- Visited by butterflies such as Eastern Tiger Swallowtail and Silver Spotted Skipper drawn to its rich nectar late in the season.
Hummingbirds
- The tubular shape of the flowers makes them appealing to Ruby Throated Hummingbirds during migration periods.
Spacing & Landscape Use
Spacing Recommendations:
- Space 12 - 18 in apart to allow for upright growth while maintaining moisture around root zones.
Landscape Placement:
- Excellent for rain gardens, stream edges, pond borders, and naturalized lowland meadows. Use to add vertical structure and seasonal bloom in moist settings.
Companion Plants
- Veronicastrum virginicum 'Lavendelturm' - Spire like flower clusters complement the vertical shape while offering contrasting pale lavender tones.
- Osmunda cinnamomea (Cinnamon Fern) - Bold textured fronds provide backdrop and structure to highlight Lobelia’s floral display.
- Actaea racemosa (Black Cohosh) - Tall white plumes and finely dissected foliage make a ghostly and elegant pairing with Lobelia’s upright spikes.
- Chelone glabra (White Turtlehead) - Moisture loving and shade tolerant with crisp white flowers that bloom simultaneously.
- Mimulus ringens (Monkey Flower) - Blue purple blooms and similar wet habitat needs make this a colorful low growing companion.