Cardinal Flower

Lobelia cardinalis

"But when vivid color is wanted, what can surpass or equal our cardinal flower? There is a glow about this flower as if color emanated from it as from a live coal."

– John Burroughs (1)

Named for the red robes of Roman Catholic cardinals, the cardinal flower is a member of the bellflower family (Campanulaceae) and depends on hummingbirds for pollination (2). The bloom period corresponds to the summer migration of Ruby-throated hummingbirds south for winter (1). It is often found in moist soil along streams and rivers and could be attractive as a border for a woodland garden. Height at most reaches about 3-4 feet, and bloom time is May-October depending on your climate zone (2).

Growth Conditions

 

Plant in sun, part shade, or shade. The soil should be moist at all times and is said to grow well in the following soil types: “Moist to wet, humus-rich soil. Medium Loam, Clay Loam, Limestone-based, Sandy, Sandy Loam, Clay” (2). Cut back after flowering (3). The plants can be mulched lightly in the winter, but be sure to tuck it under the basal leaves so they are not covered (1).

Propagation

Seeds will appear in a brown capsule. Near maturity, the capsule opens a little at the top. Check capsules at both ends of the stalk frequently to catch before the seeds fall. The seeds are an extremely fine powdery yellow. Dry them and store in a sealed refrigerated container for up to three years. Three months of cold-moist stratification in the refrigerator will increase germination rate (2). Sprinkle the seeds on a flat of dirt and dust lightly with a covering of soil. Water it from the bottom so that the seeds do not get buried down in the soil. They should germinate in one week if the soil is warm (1).

Another method is to bend a stem into the mud and fasten with rocks or sticks (2). The stem should root. It can also be grown from bud cuttings in late summer (3), or younger plants will develop around the base of the older plant each year and can be separated. However, the perennials are short-lived. It is important to plant some from seeds so all the plants do not die off at once.

Historical Use and Warnings

“Use Medicinal: Amerindians used root tea for stomach aches, syphilis, typhoid, worms. Leaf tea used for colds, croup, nosebleeds, fevers, headaches, rheumatism. Poisonous. (Foster & Duke) Roots, finely ground, placed in food said to be an aphrodisiac. (Weiner). Use Other: Used mainly in love potions. Finely chopped roots places in food as love charm. Warning: POISONOUS PARTS: All parts. Toxic only if eaten in large quantities. Symptoms include nausea, vomiting, diarrhea, salivation, exhaustion and weakness, dilation of pupils, convulsions, and coma. Toxic Principle: Alkaloids lobelamine, lobeline, and others, plus a volatile oil. (Poisonous Plants of N.C.)” (2).

Other names: Bog sage, brilliant lobelia, hog’s physic, Indian pink, red bay, scarlet lobelia, slinkweed, water gladiole, related: Lobelia fulgens, Lobelia splendens (3).

Bibliography

1. Donaldson, Cathy. Cardinal Flower—Spectacular Scarlet Blossoms That Hummingbirds Adore. Brooklyn Botanic Garden. [Online] September 1, 1999. [Cited: March 24, 2013.] http://www.bbg.org/gardening/article/cardinal_flower.

2. Lobelia Cardinalis. Lady Bird Johnson Wildflower Center. [Online] December 7, 2012. [Cited: March 24, 2013.] http://www.wildflower.org/plants/result.php?id_plant=LOCA2.

3. Lobelia Cardinalis AGM. Royal Horticultural Society. [Online] 2011. [Cited: March 24, 2013.] http://apps.rhs.org.uk/plantselector/plant?plantid=1181.