I planted last Spring and over the summer pond dropped 4 feet did not fill back up until this Spring. The following plants were fine and are flourishing this year:
Cardinal Flower (Lobelia cardinalis)
Blue Flag Iris (Iris virginica)
Arrowhead (Sagittaria latifolia)
Survey is still out on:
Pickerelweed (Pontederia cordata) which I think is starting to come up.
Monkeyflower (Mimulus ringens)
The White Turtlehead (Chelone glabra) is dead as a door nail.