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Phlox Subulata (moss pink) in landscape. Photo © Elaine Mills
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Lobelia siphilitica (Great Blue Lobelia)

Lobelia siphilitica (Great Blue Lobelia) emerging leaves in March
Lobelia siphilitica (Great Blue Lobelia) buds, flowers, leaves in August
Lobelia siphilitica (Great Blue Lobelia) en masse in August. Photo by Elaine L. Mills, 2015-08-02, Simpson Demonstration Gardens.
The underside of the corolla of Lobelia siphilitica (Great Blue Lobelia) appears pinstriped with narrow blue-violet lines and broad white stripes in August.
Lobelia siphilitica (Great Blue Lobelia) en masse at Brookside Gardens in August
Bilabiate flowers with 2-lobed upper lip and 3-lobed lower lip of Lobelia siphilitica in September
Lobelia siphilitica (Great Blue Lobelia) in residential landscape in September

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Great Blue Lobelia typically grows in moist to wet locations along streams, swamps, and meadows. It is common in the mountains of the Mid-Atlantic Region, frequent in the Piedmont, and infrequent to non-existent in the Coastal Plain. Lobelias can be impressive, especially en masse. Tried and True Native Plant Selections for the Mid-Atlantic Perennial Flowers En Masse, with Pollinator,* Close-up Height: 1–5 feet Spread: 1–11⁄2 feet Bloom Color: Blue, violet Characteristics Clump-forming perennial Stiff, erect, unbranched leafy stems Serrated, lance-shaped, medium green leaves Light to dark blue, tubular two-lipped flowers (three lobes on lower lips, two on upper) on spike-like raceme bloom August to October May self-seed to form colonies Attributes Tolerates heavy shade and wet soil No serious pests (although slugs may eat leaves) or diseases; deer seldom severely damage Long bloom time Botanical name for its supposed efficacy in treating that disease Attracts mainly bumble and other long-tongued bees and sometimes butterflies and hummingbirds Growing and Maintenance Tips Excellent Replacement for Soil Requirements: Humus-rich Lythrum salicaria - Purple Loosestrife Light Requirements: Sun, Partial Shade Lythrum virgatum - European wand Loosestrife Water Requirements: Moist, Wet Divide clumps by separating the basal offshoots from the mother plant in spring or fall as needed Use in perennial, native plant, and woodland gardens or near ponds and streams *A worn, female eastern tiger swallowtail butterfly feeds. Her dark coloring mimics that of the poisonous pipevine swallowtail and is more common in the south of her range inhabited by pipe- vines. This deception may help protect her from bird predators. Hardiness: USDA Zones 4–9 developed by Master Gardeners of Northern Virginia, serving Arlington and Alexandria Images by Elaine Mills, Meadowlark Botanical Gardens and by Mary Free (bottom right), Sunny Garden

Tried and True Native Plant Selections
 for the Mid-Atlantic

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Lobelia siphilitica (Great Blue Lobelia)

Great Blue Lobelia typically grows in moist to wet locations along streams, swamps, and meadows. It is common in the mountains of the Mid-Atlantic Region, frequent in the Piedmont, and infrequent to non-existent in the Coastal Plain. Lobelias can be impressive, especially en masse.

Learn more about other Mid-Atlantic plants: 
Tried and True Native Plant Fact Sheets

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