Dark leaves with yellowing edges.

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"Imagine no religion"
Oct 27, 2009
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I have about another week to go before harvest. for the last couple weeks the big water leaves of one plant in particular has very dark, almost purpleish leaves with yellowing edges. The leaves arnt dropping and the buds look fine. Just wondering it this is normal near harvest.

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Yes, this is normal. Depending on the strain the pant will turn varying degrees of red or purple as anthocyanins are produced using excess sugars in the leaves and begin spreading through cell fluids. The pH of the cell fluid determines the color variation, with an acidic fluid producing reddish hues, and an alkaline fluid producing blues.
No, that kind of coloring is not really normal. You generally get a yellowing of the leaves and they drop as you get near harvest because of N depletion. The purplish leaves with

What are your temps?
I have heard and read that some of the purple coloring is phenotype related but even then it has to be brought on by colder temps. Usually the yellowing off of the fan leaves towards the end of the grow happen like Goddess said, because of the lack of nitrogen(and with some strains it just does it that way). However the yellowing off is typically more uniform across the leaf rather than just at the margins. I would suspect that your coloring and yellowing are deficiency related but possibly due to nutrient lockout from low temps or PH out of tolerance.
I could be wrong on this but I remember reading somewhere that on some of the "blue" or "Purple" strains that a sudden color change toward the redish, purplish colors is actually a magnesium deficiency.
Are the leaves really yellowing bad or the parts that appear yellow more a green coming through the purpling? The purpling looks like cold to me, what temps are you at night? To me, it appears like a lighter shade of green peeking out from under the purple, but jmho In other words, looks like normal color change with added purpling from cold.
Knowing the strain would be a help in finding out if theiris a problem or not.

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