total darkness

Before you harvest I’ve read that you are suppose to give your plants 2 days of darkness. Can anyone out there clarify this for me? Some say to not water the plants so it pulls out as many nutrients as possible but I wasn’t sure about the lack of light.

Outside growing medium darkness light amount

I have 4 plants - all 80% sativa dominanth, grown outdoors in mallorca spain, humidity usually around 70-75%. I have just completed a 2 week flush this morning, and waiting for the pots to dry out a little in the sun After a few rainy days. I've got a drying room set up in the garage which is...