Bill, typical advice to new growers is to cut down to a node which you might do for some of the species or primary hybrids. Link to FAQ at end of post. My Phal flowering after being cut to a node Phal. Grown by windowsill grower. Previous year's flowering stem cut at base. Here is a link that might be useful: Old FAQ

Congrats on getting your phals to spike. That's a lot of good growing, and you should feel smug about it :). As to the single flower: Flowers on a phal spike do open one at a time. So it may be just the normal opening. Look real close at the tip of the spike: is there a little tight roundish tip? That tip often lengthens and forms additional buds, which will open while the 1st flower is still on. However, that's not the only possible scenario: it could be it's a newish plant and one flower is all it has strength for. I've had that a couple of times. In that case, be patient and your next blooming should be a lot bigger. It could be, depending on the genetics, one of those summer-bloomers that keeps developing one flower at a time over a long period of time. I've had this, too. So I would say, enjoy your flower and take it as a sign you are doing things right. Be a little patient and you may still get lots more flowers. Be a lot patient and you will get another spike with more flowers next year. As long as your phals are getting good light and put out new leaves regularly, you'll get lots of flowers from them Enjoy

The banana entomologist worked all of his working years in Central America in charge of the large plantations making sure that they were disease free. I went on a field trip to Panama with the Topical Fruit Club 10 years ago for a tour. One of our visits was to a banana plantation where we got to see how they grow, harvest and box the commercial bananas. Quite impressive. Christine

If I find them when in bloom,I try to set a pod on the scape This will keep the prolif growing and maturing as long as the scape is green I air layer the profif on expensive cultivars after setting pods. Some growers use Dap paste to cause prolifs Charlie