Yellowing leaves but whyyyy?

she is looking nice btw, she is hungry. Plants inside a grow tent usually get more intense light, heat and a higher humidity which means the plant can use up nutrients way quicker than outside. (you can check VPD online if you wanna know more about that) since you're growing organically, there is probably nothing you could do since she is almost ready to harvest, i assume. Depending on how much time she has left, maybe a foliar spray could work 15 minutes after the light's have shut off would be the best time. You can use basically every fertilizer for that, you just have to dilute it down to like 25%. if you wanna make sure maybe even lower. But don't spray the buds since it could result into bud rot. Them losing the color is usually normal in flower, you don't give fertilizer in the last weeks because you want the plant to use the nutrients that are stored in the plant, so it's really not a big deal unless you need to push like 4 or 5 more weeks. Will still be a great harvest i can tell (: