One of my favorite showy fall wildflowers is the Great Blue Lobelia (Lobelia siphilitica). This plant is commonly found in wet woodlands, floodplain forests, emergent marshes, wet meadows, and swamps throughout the eastern United States and Canada.
Great Blue Lobelia plants can reach a height of up to four feet. The upper half of the plant is commonly covered in lavender-blue to dark-blue flowers. The flowers of the Great Blue Lobelia are densely packed on a spike rising above large (2 inch wide x 5 inch long) leaves that are arranged alternately on the lower half of the stem. These blooms can be found from August to October in Mid-Michigan.
The individual flowers are tube-shaped and may be 1 to 1.5 inches long. Each mature flower has two extending "lips" on the lower side of the tube's opening - these lips provide an inviting landing zone for pollinators. The flower is mainly visited by long-tongued bumble bees. The bees force their way into the flower's tubes and use their long tongues to reach nectar deep in the flower. The flower is occasionally visited by hummingbirds, large butterflies, and short-tongued bumble bees. However, the short-tongued bumble bees often become nectar robbers- cutting a slit near the base of the flower to take nectar without pollinating the plant.
Great Blue Lobelia