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Blue Cardinal Flower Lobelia siphilitica

Other Common Name(s):

Other plants called Blue Cardinal Flower:

Phonetic Spelling
loh-BEE-lee-a sigh-fy-LY-tih-kuh
This plant has low severity poison characteristics.
See below
Description

Great Blue Lobelia is a herbaceous perennial that may grow 3 to 4 feet tall. The leaves are alternate with a toothed margin. Blue flowers first mature in mid-summer and continue into early fall. The flowers are larger than other Lobelias and have stripes on the tube portion.

This plant provides late summer bloom to the perennial border, wild garden, native plant garden, woodland garden, or naturalized planting. It is also effective near ponds or streams.

This plant was selected as the 1993 NC Wildflower of the Year, a program managed by the North Carolina Botanical Garden with some financial support from the Garden Club of North Carolina.

Fire Risk: This plant has a medium flammability rating. 

Insects, Diseases, or Other Plant Problems: Snails and slugs may damage the foliage.

More information on Lobelia.

See this plant in the following landscape:
Pollinator Garden in Partial Shade
Cultivars / Varieties:
  • 'Blue Selection'
'Blue Selection'
Tags:
#hummingbird friendly#showy flowers#poisonous#rain garden#fall flowers#native perennial#blue flowers#low maintenance#fire medium flammability#NC native#herbaceous perennial#native garden#naturalizes#pollinator plant#food source fall#NC Native Pollinator Plant#flowers late summer#Coastal OBL#food source nectar#food source pollen#Piedmont Mountains FACW#food source hard mast fruit#butterfly friendly#HS302#Audubon#NC Wildflower of the Year#herb garden#wildlife friendly#meadow#woodland
 
Cultivars / Varieties:
  • 'Blue Selection'
'Blue Selection'
Tags:
#hummingbird friendly#showy flowers#poisonous#rain garden#fall flowers#native perennial#blue flowers#low maintenance#fire medium flammability#NC native#herbaceous perennial#native garden#naturalizes#pollinator plant#food source fall#NC Native Pollinator Plant#flowers late summer#Coastal OBL#food source nectar#food source pollen#Piedmont Mountains FACW#food source hard mast fruit#butterfly friendly#HS302#Audubon#NC Wildflower of the Year#herb garden#wildlife friendly#meadow#woodland
  • Attributes:
    Genus:
    Lobelia
    Species:
    siphilitica
    Family:
    Campanulaceae
    Life Cycle:
    Perennial
    Recommended Propagation Strategy:
    Division
    Seed
    Country Or Region Of Origin:
    Eastern North America
    Fire Risk Rating:
    medium flammability
    Wildlife Value:
    Its flowers are attractive to hummingbirds and butterflies.
    Play Value:
    Wildlife Food Source
    Particularly Resistant To (Insects/Diseases/Other Problems):
    This plant has low resistance to damage from deer.
    Dimensions:
    Height: 3 ft. 0 in. - 4 ft. 0 in.
    Width: 1 ft. 0 in. - 1 ft. 6 in.
  • Whole Plant Traits:
    Plant Type:
    Herbaceous Perennial
    Native Plant
    Poisonous
    Wildflower
    Woody Plant Leaf Characteristics:
    Deciduous
    Maintenance:
    Low
  • Cultural Conditions:
    Light:
    Dappled Sunlight (Shade through upper canopy all day)
    Full sun (6 or more hours of direct sunlight a day)
    Partial Shade (Direct sunlight only part of the day, 2-6 hours)
    Soil Texture:
    High Organic Matter
    Soil Drainage:
    Moist
    Occasionally Wet
    NC Region:
    Mountains
    Piedmont
    USDA Plant Hardiness Zone:
    4a, 4b, 5a, 5b, 6a, 6b, 7a, 7b, 8a, 8b, 9a, 9b
  • Fruit:
    Display/Harvest Time:
    Fall
    Fruit Description:
    Displays from August to November
  • Flowers:
    Flower Color:
    Blue
    Flower Inflorescence:
    Raceme
    Flower Value To Gardener:
    Showy
    Flower Bloom Time:
    Fall
    Summer
    Flower Shape:
    Tubular
    Flower Description:
    Great lobelia is a clump-forming perennial which features an elongated cluster of light to dark blue, tubular, 2-lipped flowers with the three lobes of the lower lip appearing more prominent than the two lobes of the upper lip. The flowers arise from the upper leaf axils forming a dense terminal raceme atop stiff, unbranched, leafy stalks typically rising 2-3' tall. Its flowers are larger than other lobelias and have stripes on the tube portion. Blooms from July to October.
  • Leaves:
    Woody Plant Leaf Characteristics:
    Deciduous
    Leaf Color:
    Green
    Leaf Arrangement:
    Alternate
    Leaf Shape:
    Lanceolate
    Leaf Margin:
    Dentate
    Hairs Present:
    No
    Leaf Length:
    3-6 inches
    Leaf Description:
    Great lobelia has finely-toothed, lance-shaped, light green leaves (to 5" long). The alternate, stalkless leaves are 2 to 6 inches long.
  • Stem:
    Stem Is Aromatic:
    No
  • Landscape:
    Landscape Location:
    Meadow
    Naturalized Area
    Riparian
    Woodland
    Landscape Theme:
    Butterfly Garden
    Native Garden
    Pollinator Garden
    Rain Garden
    Design Feature:
    Border
    Attracts:
    Butterflies
    Hummingbirds
    Pollinators
    Resistance To Challenges:
    Deer
    Wet Soil
    Problems:
    Poisonous to Humans
  • Poisonous to Humans:
    Poison Severity:
    Low
    Poison Symptoms:
    Nausea, vomiting, diarrhea, salivation, exhaustion and weakness, dilation of pupils, convulsions, and coma
    Poison Toxic Principle:
    Alkaloids lobelamine, lobeline, and others, plus a volatile oil
    Causes Contact Dermatitis:
    No
    Poison Part:
    Flowers
    Fruits
    Leaves
    Roots
    Sap/Juice
    Seeds
    Stems