Depends, If outdoor. should be finished by then. If indoor its really when you switch to 12/12 schedule. but have found the first week really don't count. I get ready about week 8 of flower. Also very strain dependant. Sativas are a hell-a-va lot longer than Indicas. It all depends. Harvesting way too early sacrifices Potency and Yeild. Harvest sorta early. Uppy heady high. All depends, but when it comes to growing bud Time is probably the biggest key for harvest time.