I have been told to water Vanda roots until their color become
completely dark green.
I have tried to water the roots 5 times with 5 minutes interval;
I even soak one of them in a glass for 30 minutes.
I can not make them turn completely green; there are still white
blotch on the roots especialy near the root tips.
Is there a good way to saturate the root until completely dark green
(I do not use any potting media)?