When I'm repotting one, what do I look for in the roots? Do old roots have to be cut out like a phal. or not? All of mine but 1 bloomed in the winter, but I have one that is in spike now for some reason. It did not bloom last winter. But I have one that looks like it needs a new pot...also is there anything I need to add to the mix when repotting...like what kind of mix do they prefer?