Den.New Spike on Old Growth?

[rich63]

I know this seams like a simple question.I was under the impression that hardcane Dens. only would produce new spikes from new growth.This plant was purchase last Sept.This is one of afew Den.s that hasn't produced any new growth or any keikis.As you can see where the old spike was and the new spike coming up ? Is this very common ? Thanks,Rich