Bmollyanswered grow question a year ago It's normal for the leaves to turn yellow towards the end of the cannabis plant's flowering period. This is because, as the supply of nutrients in the irrigation water is reduced or eliminated, the plant begins to use up the nutrient reserves stored in its leaves.
During this stage, the plant prioritizes nutrient transfer to the developing buds, which can result in nutrient depletion in the lower leaves. As a result, the leaves may turn yellow and eventually fall off.
Although yellowing leaves can indicate that the plant is using up its nutrient reserves, it's still possible for the buds to continue fattening. At this point, it can be beneficial to continue watering with just plain water for an additional one or two weeks to allow the plant to fully utilize its nutrient reserves.
Your plants look lovely and healthy, so there's no need to worry. It's normal for older leaves to show signs of nutrient depletion.
Best regards, and I hope I've been helpful to you.