Is the number of spikes pre-determined?

[nogreenthumbs]

I don't think these will necessarily always do the same thing twice. I think there may be some plants that have a tendency to multiple spikes and some may not, but I don't think a double spike plant will always throw double spikes, and it may be different the time after that. How happy and healthy the plant is with it's environment will probably also have a lot to do with how it grows and blooms.

These things don't have hard and fast rules, they have guidelines and can and will do different stuff just to keep us on our toes.

Having the one spike break, probably wont' have any effect on future spiking. If anything, you saved the plant having to put a lot of energy into the other spike which may have helped it adjust to the new environment and stress of things changing.