Plz help my baby is dying

Can anyone plz tell me what is wrong with my baby? It started off at the bottom only affecting new growth then it moved to older leaves and finally started creeping upwards. I think it's N deficiency but not sure and don't want to over dose. I currently feed botanicare cns17 3-1-2 grow 15 ml per gallon. Water 8 gallons about every four days as temperature is reaching triple digits. Outdoor plant in a 5'x4 space if anyone could please help

The last four photos are after i prunned all the dead leaves. It was planted on the last week of march please feel free to give any advice. The strain is maui wowie. I am thinking of tying down all the b ranches with bamboo sticks due to the weight of them.