'Goldsturm' is a great plant, bright and reliable. The height can vary depending on location and probably moisture availability. It does really hate to get overly dry, especially when flowering. It also self-seeds, though, which can be a plus or a minus depending on one's viewpoint. Deer will occasionally munch on it here, but this year some plants are being seriously attacked by voracious rabbits! They are only going for the small plants such as volunteers, not for the established ones which are too big for them.
They are just starting to flower here in Ontario now, so earlier than Elaine's.