the shoots arent always going to be a bright fresh color.... It could simply be the plant genome or that hte humidity is high. I have had expereience with an extremely humid room where growth was around 2 inches a week!!! it grow very slowly and had beetles everywhwere. When i brought it outdoors, it literally grew 8 inches in the first week out there. So check ur humidity, dont overfertilize the young ones, and look for more significant symptoms if any.