Hi its the "regular aging "of the Plant. Chloprophyll goes back and the Colours appear.. its called " autumn leaves". Your girls is absolutely ok. I like that stage very much because its the promise to harvest soon.... enjoy the " golden days" with your Girls. If you stopped feeding her, you can give her molasses to feed the microbacteria in the soil, that helps her to devour the remaining fertilisers in the soil. Happy harvesting days soon