I have a rescue Phal that I acquired in Dec 2015 - one of those plants supplied monthly to an office then discarded at the end of the month. Leaves are very long (makes me think of basset hounds) and flower spikes are very tall - leaves much longer and spikes taller than Phals I buy from stores.

Anyway, when I took out the Phals, there were two in the pot. Over 90% of the roots were rotten. I trimmed those off and repotted later in 2 separate pots - Rescue 1 and Rescue 2. Eleven months later, Rescue 1 has grown 2 long leaves and lots of roots deeply into the substrate.

Rescue 2, however, has grown 3 very short leaves (two are 3-inch long, one is 2-inch long) and 5 roots that don't grow any longer. At first, the roots seem to be stuck at 1 inch, never wanting it seems to dive into the substrate. I propped up and arranged the substrate so that the roots are in contact with it. That seemed to help a bit. Most of the roots grew longer, up to about 2" then stopped. So, unlike Rescue 1, Rescue 2 is not firmly attached to the substrate because its roots never grew that long to spread throughout the substrate. The roots look plump and healthy though.

Rescue 2 also formed a basal keiki in Aug 2016. The basal keiki now has 3 leaves (one is 2", two are 1").

Rescue 1 and Rescue 2 have the same substrate and are indoors on the same window sill (facing east). They both get watered approximately every 7 days.

Why is Rescue 2 having a hard time growing its roots? I have 6 Phals and this is the only one that is having a hard time growing its roots. :( What can I do to help it develop its roots?