Personally I don't flush the right way I don't think - I would start the flush in a couple days if the plant in the photo was mine. I run a slowly diluted nute mix over the course of two weeks. I use coco. It seems that this helps clear the system way more while keeping the plant happy.. for that smooth smoke and white ash I was looking for (if I catch the cure good). Slowly diluting the nutrient mix will leave my soil cleaner than if I run straight water flush. I stem split and leave it in the dark to dry out. I might not be the best one to answer that question for ya I am a risky grower.