Cardinal flower (Lobelia cardinalis) is a perennial native to North America. Beneath the flower spikes are numerous dark green leaves, tapered at both ends. It grows two to four feet tall, stout and erect. It is the favorite of the ruby-throated hummingbird, who obliges as a pollinator. This specimen seems to be doing well in a fairly sunny location, but this species probably grows best in filtered light in moist soil.