BTW checking the pistls isn't that accurate, due to many vets harvesting WW whith plenty of white pistles still...the colour will vary from strain to strain.
tckfui is correct. Let the plants get as many hours of darkness as possible prior to sun rise, this will make sure all or almost all of the starches, and sugar, and nitrites are in the root system. Just cut the stem, then manicure it in the light prior to drying...once the stem is seperated from the roots the plant can see light because it cant pull nutes any longer.
For indoor growers a little trick I learned is using green x-mas lights...plants can't process light in the green spectrum, so now your able to see, the plant still acts as though its in total darkness

That little trick prevents tripping over stuff, and falling on plants in your room, or closet lol