Introducing cold for color. Yield?

Hey everyone I’ve got some purple haze in a grow box that’s 3 weeks into flowering. I’m introducing cold temps at night low 40s (outside temps from open window)

With its genetics, cold temps should change her to purple colors. Would this effect my yield? This is the first time I’m trying this. I average 6 ounces every harvest. I’m curious if the cold temps result is less yield.

Interesting question, I have some purple haze seeds and was thinking about waiting till the end of summer to grow them so I can have more control over the temperature.

I’m harvesting mid June so I’m relying on the cool spring nights. Average 40-50. Lowest 35.

Temps down in the 40s will most certainly stunt growth, especially if you're in a non-hydro setup where you can't control the temperature of the medium.

You'll be looking at odd growth patterns, smaller buds, and overall stunted growth.

I was running at 52F in my basement over the winter, and noticed all of what I've said here up until I got my lights-off temperatures up to 58-60F.

They look healty update with some pics please when the start budding

spek9 said:

Temps down in the 40s will most certainly stunt growth, especially if you're in a non-hydro setup where you can't control the temperature of the medium.

You'll be looking at odd growth patterns, smaller buds, and overall stunted growth.

I was running at 52F in my basement over the winter, and noticed all of what I've said here up until I got my lights-off temperatures up to 58-60F.

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I’ll keep that info in mind. I heard that’s the temp you wanna hit for color change. Gotta figure that’s about Fall night temps. Also my day temps are 70-75. For 12 hours that should warm up the soil enough to hold heat for the cool nights. This is more of an experiment. But if it starts to look like she’s not budding as fast I will bring back warmer temps

Quinteli said:

They look healty update with some pics please when the start budding

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I’ll try to remember lol. That picture was from last week. I take one every Wednesday.

Color comes from genetics not temperatures. The only thing low temps will do is help change the color of the leaves. You smoking leaves? No.

if their going from day temps of like 78-80 give or take going to 40s really gonna stunt the shit out of your plant

JustDreamin said:

I’ll try to remember lol. That picture was from last week. I take one every Wednesday.

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All your doing is slowing growth. I promise. This bud was never under 65.

JoeBlow5823 said:

All your doing is slowing growth. I promise. This bud was never under 65.

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some nice foxtailing tho were u running full power all the time or did u bump it down at the end? looks like good bud doe.

JoeBlow5823 said:

All your doing is slowing growth. I promise. This bud was never under 65.

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It’s clearly purple from the Monster Energy drink!

Gond00s said:

some nice foxtailing tho were u running full power all the time or did u bump it down at the end? looks like good bud doe.

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Yeah full light till finish, it was to much. Im learning autos dont thrive on excessive light as much as photos. Switching to photos next round.

Wattzzup said:

It’s clearly purple from the Monster Energy drink!

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Monster is yellow. And i only feed my plants Brondo. Its what the plants crave.


These were all kept in the 65-75 range their entire life. None of the purple ones had any sort of good potency.

JoeBlow5823 said:

These were all kept in the 65-75 range their entire life. None of the purple ones had any sort of good potency.

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I feel like that might be the auto part that affected the potency i might be wrong but I've ran some autos pretty well just they were not as strong hitting but they finished fast so maybe that could be it. got my mcc harvest and in jars looks good very cookie dom.

JustDreamin said:

Hey everyone I’ve got some purple haze in a grow box that’s 3 weeks into flowering. I’m introducing cold temps at night low 40s (outside temps from open window)

With its genetics, cold temps should change her to purple colors. Would this effect my yield? This is the first time I’m trying this. I average 6 ounces every harvest. I’m curious if the cold temps result is less yield.
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Purple colors often don't appear until the last 2 weeks of flower, sometimes in the very last week of flower in very ripe bud.


Dropping night temps now is a very bad idea, it will possibly create extra stretch and will effect yield.


6 days later


Genetics mostly determines color as does environment to a much lesser extent, and you should never try force it because doing so will affect quality and yield, as the purple color is a sign of green chlorophyll breaking down and you don't want that happening too soon as that chlorophyll powers your plants carbohydrates and in-turn yield .

Just Grow them the best you can keeping night temps warm, and if they are not purple enough for you, change the strain, many purple strains dont go purple indoors and thats totally ok..

JoeBlow5823 said:

All your doing is slowing growth. I promise. This bud was never under 65.

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What strain I's this?

I’ll close the window then. The last grow I did of purple haze I didn’t get any purple colors.

RangiSTaxi said:

Purple colors often don't appear until the last 2 weeks of flower, sometimes in the very last week of flower in very ripe bud.


Dropping night temps now is a very bad idea, it will possible create extra stretch and will effect yield.

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6 days later
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Genetics mostly determines color as does environment to a much lesser extent, and you should never try force it because doing so will affect quality and yield.

Just Grow them the best you can keeping night temps warm, and if they are not purple enough for you, change the strain, many purple strains dont go purple indoors and thats totally ok..

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What strain?

Thanks for the input. I’d rather have good yield oppose to some color.

Quinteli said:

What strain?

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Alaskan Purple