Loss of roots of phalaenopsis when there is change of substrate

[Merita]

Another doubt, when the roots begin to deteriorate, then you have to remove the plant again and cut those roots?

[Ray]

Originally Posted by Merita

Another doubt, when the roots begin to deteriorate, then you have to remove the plant again and cut those roots?

In my experience, that depends upon the degree of difference in conditions, the extent of the failing root system, and the potting medium.

For example, for a plant with a moderate root system moved into a good, open medium, as they fail and decompose, they release nutrients and the broken-down bits are flushed away with good watering. If, on the other hand, the system was extensive, and/or it all dies at once, and/or the medium does not freely flush (sphagnum), it may require unpotting and repotting to get rid of the "cesspool" it has created. In those circumstances, I trim the old roots before repotting - another reason to make sure there are new roots emerging.