Will cardinal flowers come back next year or do new plants have to be obtained? Should the plant be cut off at the ground or leave it alone?
Certified GKH Gardening Expert
These are perennials, and they will also tend to self-seed if they flowers are left on after they die. You may either cut the dead flowers off or leave them, but it is not necessary to cut them down.
Here is an article for more information: https://www.gardeningknowhow.com/ornamental/flowers/cardinal-flower/growing-cardinal-flowers.htm