I have a dancing lady...maybe 8 years old...has performed the same every year. But this year the spikes are so long...4.5 ft..that 3 spikes have broken. Any clues as to why? I don't think I have altered their care in any way.
When you stake them, don't bind them too tightly... let them arch. But when they are that long, some support is helpful. (If you state too tightly and too far down, then can try to arch and end up snapping if they are heavy with flowers)