I agree with the keeping the plant green comment. I'm guessing you have another 2 weeks though. If you don't have one already, get yourself a hand-held microscope with a light at Radio Shack or your hydro-store.....they're around $15. Depending on how much couch lock you want, wait until the first sign of amber before chopping. Personally I now chop at almost all cloudy....very little clear.