Making a Phal make new roots

[zygostates]

Hello.
I have a Phal that was given to me to try to make it produce new roots. The plant is fairly large but for some reason the plant broke/rotted off from the roots. I have keep the plant "top" in a zip lock bag for a few weeks and nothing has happened other than a new leaf has started growing....but this orchid has no roots developing still. Soaking it in sugar water and Super Thrive tonight in a zip lock bag. Any suggestions?

[Maua]

Hi, I had a Phal given to me a year ago that had been
overwatered and rotted the roots. I cut all the rot out, let it dry off for a couple of days then placed what was left on some orchid mix in a pot standing in a saucer with stones in it. I watered it carefully and made sure the saucer had water to create some humidity -- and now it has sprouted roots and is showing signs of a new leaf. Hope this helps.