Its also a myth to cut off Nitrogen.
All Nitrogen is to a plant is>?????
PROTEIN.
Humans eat Protein/Chicken, Fish, beef, pork, beans, and rice, and turn it into Nitrogen. Plants skip this process. Protein means?? Of First Importance. Protein is essential for cell division/Mitosis, Immune System, and all Metabolic Processes are dependent on Protein.
Going by Tissue Analysis an 8 weeks flowering weed plant needs increasing amounts of EVERYTHING until the 6 week mark, when nutrients are cut by about half.
They need a MPK boost ( 0-52-34 ) in weeks 2.5-4, and a Sulfur/Mg boost in weeks 5-6. All the while the Base nutrients are Increased until week 6.