I have several Phalaenopsis orchids, species and hybrids. I have NEVER cut a green spike, I have found at least with mine, that most of the time the spike won't die, and will branch off from the original spike and flower again. And blooming, branched Phalaenopsis orchids are gorgeous! Only one of my Phal's spikes, or stalks as you called them died down, and that was only half way. I cut with sharp sterilized scissors, and put ground cinnamon on the cut to prevent infection. Blooming takes a lot of energy, and it would be best to not "force" the plant to bloom, it will on it's own and will soon enough with the right conditions. I hope this helps!