marijuanajoe1982
Well-Known Member
I always flush. I also understand how in the fall, when nitrogen levels are down, the plant uses its own nutrient stores. This causes the chlorophyll production to stop, which sucks the green right out of the leaves. However, there is more to it than just that. Temperature seems to control the intensity of the purple, or perhaps its exact color of purple. It also seems to be related to strain. I saw a pretty experienced grow journal for the Violator Kush from Barney's (pretty purple in the picture) that, when completely done correctly, had no purple on it at all. It had lots of yellow fan leaves and other leaves had also turned yellow, but did not show any purple. The dude was actually a little bummed, because he wanted them to be purple like in the picture. He also had high grow room temperature, and was told by the seed company that with lower temps at night, this could be achieved.What happens when the temps get colder is called nutrient lockout. What your seeing is the lack of chlorophyll (green) production which allows the other colors to be seen. Same thing with trees. The color is always there. You just don't see it because it is masked by all the green chlorophyll.
So any hidden colors can be brought out by cutting out all of your nutrients before harvest (flushing). Flush long enough and you will see all kinds of beautiful colors you never see normally.
Flushing also makes your bud taste sweet. I use Clearex for the first 24 hours and then straight water for at least 2 weeks. Earl flushed a White Widow plant for 6 weeks and it turned totally purple!
Personally, I have a strain that needs about 50 degree nights or a little below to get a beautiful purple/indigo. I've grown it outside and I got dark purple leaves with light green veins, indigo and light green calyxs. It was gorgeous! the next year, same variety, but it was a really warm fall, and there wasn't really any purple. Dark green leaves with light veins, and light green calyxs. the fan leaves and others had turned yellow from the nutetrient defeciencies that these plants go through that time of year, but it did not bring out the purple. Trust me, this is species specific. Some need no low temps at all to get purple, but some do. The ones that turn purple anyway would turn a darker or different color of purple if grown in colder temps. Genetics and temperature have just as much to do with it as the natural change that happens as plants divert energy elsewhere in the fall. So you are correct, there is just more to it than that. Temperature can play a major factor in some breeds, particularly the ones with just a little purple coloring.
Also, keep in mind that buds dont turn yellow as they are where the nitrogen and other goodies go to after leaving the leaves and turning them purple. The buds still have chlorophyll in them, as far as I understand. So in cases where your strain has calyxs that turn purple, you will probably need to lower temperatures to get the really pretty coloration on the buds that you want. You could also leave the fruit on the vine for a few more weeks and let it leach out naturally. However, it is pretty widely suspected that temperature can act as a catalyst in regards to the exact coloration. So I would rather just use a catalyst to speed part of the process up. So basically, it is a combination of 3 things: nature, genetics, and temperature. Not just nature. Thats what I've learned since posting this thread. out.
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