I would like to know if it was okay for a plant to have yellow leaves at max 5 week flowering ? I have tried givin her a nitrogen boost did nothing , I even gave a little dose of calmag in the last 3-4 watering.. plant is a pineaple express at about 7.5-8 feet tall.
Yes it's normal for the leaves to start yellowing midway/towards end of flower. My outdoor plants do the same thing but it does it differ among strains.
Plants do tend to yellow torwards the end of flowering. As there drawing nutrients from every angle. The fan leaves are storage banks if u will of nutrients. As the plant drains the leaves they will yellow. The fact that its most all the leaves makes me think thats what it is. Its not just new groth tops or bottoms so i think ur good dude. Congrats it looks good.
As it finishes you might want to support the colas as it finishes so you don't have any snapping off. Otherwise looks good . My current 6 Jock Horror Autos, coco coir grow