This is the blue-flowered species in the famous wild lobelia family. This one is a grand 3 to 5' plant that quickly forms attractive colonies in light woodland or other shady spots. (Allow the flowers to drop their seeds in fall, and you'll have a big group of plants in no time.) Unlike its cousin, the more showy red Cardinal Flower, which holds its flower stalks above the leaves, Great Blue Lobelia opens sky blue midsummer flowers in the axils of each upper leaf, and then continues blooming for weeks and weeks. It also sends out side shoots, resulting in striking blue bloom on a candelabra-like plant.