Struggling to keep plant green

I’m growing Big Jack seeds and they are into the second week of flowering. Some are planted directly into the ground and some are in 15 gallon fabric pots with topsoil. Using General Hydroponics Flora Nova Bloom and following the directions on the bottle. Just can’t seem to stop leaves from going yellow and dying. Please help.

Alot of people are going to probably shit on this idea but I will tell you I learned it from a Humboldt county OG grower and it 100% works every time. Go get a 10$ bag of ironite from ace hardware, throw a few handfulls on the rootbase, water it in and check it the next day

Large sun leaves, the plant sheds those this time of year. Normal.