Leaves are turning yellow!

If it is around week 5 of flowering it’s called a Die Back, it happens when the plant didn’t get enough Nitrogen during the stretch, it’s moving its Nitrogen to save the tops. Adding Nitrogen at this stage is too late, the roots are processing P-K. If it is around week 7-8 of flowering it’s called the senescence, it’s the end of the cycle and the plant is naturally fading, almost ready for harvest.