I constructed the prototype in about 2 hours. The initial charge lasted 12 hours but it has been showing low power since. The output on the panels was only 9V and i believe this is the issue that is causing the batteries to not change. I have hooked the panels up in parallel to combine the current or 6watts.
My next set is to measure the output of the panels in full sunlight and take a lumen reading as well. If the voltage is low (assuming 3v) I will add the need voltage amount (3v) with that type voltage solar panel (3v) in series to make the needed 12v.
This seems very cool, but yes, it is indeed as Jonathan Perry-Houts says. You would need a uv led or something.... here is an overkill lamp to give an idea:
http://www.plantengineering.com/single-article/ultraviolet-led-light/97528e8d5e136c5cd385903cc8792647.html