Two of my phals -- Phal. Baldan's Kaleidoscope 'Golden Treasure and Phal. Ox Firebird are currently in spike. When they both ended their last blooming cycles, I did not cut the old spikes, but left them on to see if they would either dry up or rebloom. Neither of these things happened, but instead new spikes appeared next to the old ones on each plant.

Right now the new spikes are each about 4 inches and 7 inches long and growing well, and the old spikes are still there nice and green. Should I cut the old ones off at this point to direct all the maximum energy to the new spikes, or will that do more harm than good? Any chance that the old ones might be triggered to spike at this point?