Stickanswered grow question 6 years ago At least 10 days, less will result in a chemical taste in your buds that would certainly make you cough when smoking. Don't forget that even when flushing, your PH needs to be adjusted (7.5 is really strong, I recommend you to lower a bit to 6.2 - 6.5). You better start flushing early and watch trichomes with a magnifier everyday, so you can find the perfect day to cut your branches. I'll be around, good luck with this baby bro, can't wait to see your final weight and smoke report !