How do you know if its flushed properly?

hi when i flush do i need to wait for the plant to start turning yellow b4 cutting it down?

You shouldn't see any decline in plant quality after flushing (first 24 to 48hrs can't be counted because the plant is still dealing with the "fert hang over" it was given and making internal adjustments, but in my experience when I have flushed it can take days to show any signs of growth again. I mean on average a week sometimes even two (depends on where in the grow it is at), but you shouldn't see, after 24 to 48hrs worth, of your plant getting worse...if you flushed properly.

Any more specifics may help?

will they turn yellow or start turning yellow after you flush the nutes out??