Alphabetical Plant Listing

Lobelia siphilitica (Great Blue Lobelia)

Great Blue Lobelia, Big Blue Lobelia, Blue Cardinal Flower, Blue cardinal flower, Great Lobelia , Tall Blue Lobelia, Virginia Bellflower, Vomit Root


A North American native that is perfect for the late summer garden, Lobelia siphilitica (Great Blue Lobelia) is a popular, upright perennial which produces long-lasting spikes of bright blue flowers atop a finely-toothed, lance-shaped foliage from late summer to mid-fall. Quite an architectural plant that adds vertical interest to the landscape. The nectar and pollen of the flowers attract primarily hummingbirds, bumblebees, and other long-tongued bees. Extremely hardy, low care, and fairly pest and disease-free, Great Blue Lobelia tends to be short-lived, although it may self-seed in ideal growing conditions (without becoming invasive).

  • Generally growing 2-3 ft. tall (60-90 cm) and spreading 12-18 in. (30-45 cm), this clump-forming Lobelia thrives in rich, humusy, medium to wet soils in full sun to part shade. Appreciates some shade from the hot afternoon sun and loves a lot of moisture. Keep soil moist during summer dry spells. Can be grown in water to 3 in. deep (7 cm).
  • A welcomed addition to beds, borders, wild gardens, woodland gardens, cottage gardens, and near ponds or streams.
  • A magnet for hummingbirds, butterflies, and beneficial insects, it is deer and rabbit resistant!
  • Deadhead for a neat appearance, encourage rebloom or prevent any undesired reseeding. Pinch back for bushier and more compact plants. Do not cut back in fall, mulch lightly. Divide clumps in spring if needed.
  • Ingestion may cause discomfort.
  • Toxic to dogs, toxic to cats, toxic to horses.

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Requirements

Hardiness 4 – 9
Heat Zones 1 – 8
Climate Zones 1, 2, 3, 4, 5, 6, 7, 8, 9, 14, 15, 16, 17
Plant Type Perennials
Plant Family Lobelia
Exposure Full Sun, Partial Sun
Season of Interest Summer (Late)
Fall
Height 2' – 3' (60cm – 90cm)
Spread 1' – 2' (30cm – 60cm)
Spacing 12" – 18" (30cm – 45cm)
Water Needs High
Maintenance Low
Soil Type Chalk, Clay, Loam, Sand
Soil pH Alkaline, Neutral
Soil Drainage Moist but Well-Drained, Moisture Retentive
Characteristics Showy
Native Plants United States, Midwest, Illinois, Indiana, Iowa, Kansas, Michigan, Minnesota, Missouri, Nebraska, North Dakota, Ohio, South Dakota, Wisconsin, Northeast, Connecticut, Delaware, Maine, Massachusetts, Maryland, New Hampshire, New Jersey, New York, Pennsylvania, Vermont, Rocky Mountains, Colorado, Wyoming, Southeast, Alabama, Arkansas, Georgia, Kentucky, Louisiana, Mississippi, North Carolina, South Carolina, Tennessee, Virginia, West Virginia, Southwest, Oklahoma, Texas
Tolerance Deer, Wet Soil
Attracts Bees, Birds, Butterflies, Hummingbirds
Garden Uses Beds and Borders, Bog Gardens, Ponds and Streams, Rain Gardens, Water Gardens
Garden Styles City and Courtyard, Coastal Garden, Informal and Cottage, Prairie and Meadow

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Great Plant Combination Ideas with Lobelia


Picture courtesy of Botanik Foto

While every effort has been made to describe these plants accurately, please keep in mind that height, bloom time, and color may differ in various climates. The description of these plants has been written based on numerous outside resources.


Requirements

Hardiness 4 – 9
Heat Zones 1 – 8
Climate Zones 1, 2, 3, 4, 5, 6, 7, 8, 9, 14, 15, 16, 17
Plant Type Perennials
Plant Family Lobelia
Exposure Full Sun, Partial Sun
Season of Interest Summer (Late)
Fall
Height 2' – 3' (60cm – 90cm)
Spread 1' – 2' (30cm – 60cm)
Spacing 12" – 18" (30cm – 45cm)
Water Needs High
Maintenance Low
Soil Type Chalk, Clay, Loam, Sand
Soil pH Alkaline, Neutral
Soil Drainage Moist but Well-Drained, Moisture Retentive
Characteristics Showy
Native Plants United States, Midwest, Illinois, Indiana, Iowa, Kansas, Michigan, Minnesota, Missouri, Nebraska, North Dakota, Ohio, South Dakota, Wisconsin, Northeast, Connecticut, Delaware, Maine, Massachusetts, Maryland, New Hampshire, New Jersey, New York, Pennsylvania, Vermont, Rocky Mountains, Colorado, Wyoming, Southeast, Alabama, Arkansas, Georgia, Kentucky, Louisiana, Mississippi, North Carolina, South Carolina, Tennessee, Virginia, West Virginia, Southwest, Oklahoma, Texas
Tolerance Deer, Wet Soil
Attracts Bees, Birds, Butterflies, Hummingbirds
Garden Uses Beds and Borders, Bog Gardens, Ponds and Streams, Rain Gardens, Water Gardens
Garden Styles City and Courtyard, Coastal Garden, Informal and Cottage, Prairie and Meadow

Great Plant Combination Ideas with Lobelia

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