How many weeks before harvest should I lower temps at night for purple strains?? Ive kept the temps around 74 throughout the veg and flower so how many degrees should I drop it?? Should I drop temps during the day a little too?? How long should I keep dropping temps before harvest??

In my experience with purples the bulk of color change happens in the last 1/4 or so of the flower cycle.Lowering temp has biggest affect during this time not as much before.Plant maturity is tied to color also.I try to keep my room at 60 or below if possible.Keep the temp as low as possible 24 hrs a day.

thats not good advice, he was right in saying that they get the last bit of color near the last few weeks of flowering though...(usually in the last 2-3weeks of flower)

If you would like a purple color its best so start with a strain that turns a purple color. If you would then like it to be more colored by temp changes (which do really nothing for the bud but make it grow worse because of low temp conditions)

The best way to do that is to lower the daytime temps in the room to around 60F. Then @ night you want it to drop 10 to 15 degrees lower than the daytime temp to a temp of 45F-50F

I would actually suggest finding better genetics though for the best purple colors without having to screw around with temp changes. Having a cold or hot room lowers yields terribly and is actually the most common factor for low yields.
Im growing this strain out in my room now, it got this purple in a room that was 78 degrees Fahrenheit. Pm me if you want more info on this general subject or the strain Im growing

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my experience is lower it 10 degrees during the final few weeks of flowering (lower it during the light off period). i have a grand daddy purple urkel hybrid that is very nice purple color. i will post pics of them when i can...

and if you like hermie plants.... alter temps.

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OG KUSH
Bleezy's Grow Journal Bleezy's Vidoes Updates http://www.youtube.com/user/Bleezyg420

if the purple your talking about is granddaddypurple it will flower on its own at the end without ac.Good luck

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Boycott kellogs,eat generic ricekrispies!

ive had GDP not turn purple in the summer so sometimes that is not always the case.

did you two not see this picture? The plant was in a room of 75 dgree temps its WHOLE life.

you are exactly right. If you want a purple strain get some purple genes and they will do it all on their own.

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Its so true. temps have little effect on color. Nor does age. So lowering the temps for the last 2wks is just a bad idea. It wont do a thing good for your color. Its all in the plant

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we have traveled this way before but there is still much to learn...My indoor grow in Hawaii http://www.rollitup.org/grow-journal...ow-indoor.htmlmy White Russian grow. http://www.rollitup.org/grow-journal...finish-31.html

+rep for someone else that knows what they are talking about