Cardinal Flower (Lobelia cardinalis) is a perennial which typically grows in moist locations along streams, sloughs, springs, swamps and in low wooded areas. A somewhat short-lived, clump-forming perennial which features erect, terminal spikes (racemes) of large, cardinal red flowers on unbranched, alternate-leafed stalks rising typically to a height of 2-3 feet. Tubular flowers are 2-lipped, with the three lobes of the lower lip appearing more prominent than the two lobes of the upper lip. Finely-toothed, lance-shaped, dark green leaves (to 4 inches long). Late summer bloom period. White and rose colored forms are also known.
The blooming period occurs from late summer to early fall, lasting about 1–1½ months. The small seeds can be carried aloft by the wind. The root system consists of a taproot.
Habitats include wet prairies, prairie swales, openings in floodplain and bottomland woodlands, soggy meadows along rivers and streams, gravelly seeps and springs, borders of ponds, edges of small marshes, and ditches. These habitats include both sandy and non-sandy areas. Cardinal Flower is often found in sunny areas near sources of water, or it is found in open woodland areas where moist depressions occur.
Easily grown in rich, medium to wet soils in full sun to part shade. Needs constant moisture. Tolerates brief flooding. Soils should never be allowed to dry out. Tolerates full sun in northern climates, but appreciates part afternoon shade in hot summer climates. Root mulch should be applied in cold winter climates to protect the root system and to prevent root heaving. Mulch will also help retain soil moisture.