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Lobelia cardinalis

cardinal flower

Plant Details

Common Name: cardinal flower
Family: Campanulaceae (bellflower family)
Mature Height: 5 - 10'
Sun Requirement: Sun, Sun to part shade, Part shade to shade
Moisture Requirement: Medium - moist, Moist
Flower Color: Red
Bloom Time: Mid summer (July - August), Late summer (August - September)
Seed Collection Date: Late summer (August - September), Fall (September - October)

Lobelia cardinalis Cardinal flower
Lobelia cardinalis Cardinal flower
Lobelia cardinalis Cardinal flower
Lobelia cardinalis Cardinal flower
Lobelia cardinalis Cardinal flower
Lobelia cardinalis Cardinal flower
Lobelia cardinalis Cardinal flower

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Etymology

Lobelia is Latin, honoring Matthias de l’Obel, (1538-1616), a physician/botanist who worked on a system of plant classification by leaf variety; cardinalis is Greek, and alludes to the brilliant red of the flower.

Native Habitat

Moist soils at the edge of woodlands, ravines, meadows, swamps, flood plains.

Garden Uses

The flowers, which bloom through late summer, are a very showy red color and aromatic. They are best planted in consistently moist woodland areas and borders, including pond or stream edges, rain gardens and boggy areas. They tolerate brief periods of flooding, but not drought. They may benefit from mulching, both to prevent heaving in colder areas and to retain moisture. Primary plants are fairly short-lived, but will reseed into areas they find suitable.

Overview

Cardinal flower is a showy, red, summer-blooming perennial that prefers moist to wet soil in sunny to shady areas, and is often seen along stream banks and other wet areas throughout the eastern and southern US.

Leaves and Stems

Leaves are 4" long, finely-toothed, dark green, lanceolate and alternate along stalks that are erect and non-branching, but often in clusters.

Flowers

Flowers appear on 8' long terminal spikes (racemes) of scarlet blossoms, each with a dominant lower lip divided into 3 spreading petals, and an upper lip of 2 slimmer petals; all are fused together on a tubular base. Each flower has 5 stamens and 5 sepals.

Fruit/Seed

Small seeds form within a capsule that changes from green, to bluish, then brown as it dries and opens. Seed often remains in capsules on standing stems long past flowering.

Animal Associates

Hummingbirds are a primary pollinator of this plant as the tubular neck of the flower dissuades insects. Cardinal flower is mildy deer resistant.

Propagation

Bend a stem of a growing plant down to a consistently moist area, and fasten with a rock or stick to root. Seeds can be collected when the seed capsule dries and opens slightly at the top. Store cleaned seeds in a sealed, refrigerated container (cold, moist, stratification) for at least 3 months.

Ethnobotanical Uses

Native Americans made tea from the root of cardinal flowers for stomach aches, syphilis, typhoid, worms. Leaf tea has been used to ease colds, croup, nosebleeds, fevers, headaches and rheumatism. The plant is toxic to humans if large quantities are consumed.

Garden Location

Library Garden (see garden map)

Anecdotal Information

We get a few cardinal flower plants in unpredictable places in the Library Garden every year which are progeny from our original planting.

Sources

Lady Bird Johnson Wildflower Center

Missouri Botanical Garden

Native Plant Trust

Plant Profile by Kate O'Dell