I'm actually glad you asked me that. As I pondered my response whilst laying on my flower room floor taking a little breather I asked myself the same question. So I pulled back some perlite to expose roots at the top of the container and snapped a picture:
Dang it, now I am worn out and dont have the energy left to give you a proper come back. The short version is that you have proven my point for me, so I will just stop here

LOL sorry, Im tired and stoned, but Im also mostly serious. Unfortunately, the details will have to wait....
I will give you a hint of whats to come though ...... notice that the roots up top are brown, but the perlite is still white....
I hope the OP doesnt mind our carrying on like this. Im sure enjoying it
