Blue lighting during last 3-7 days of flower?

oldfogey8

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I was doing some reading this morning about light wavelength and it's effects on cannabis and came across this on heliosprectra.com

Grower Trick: Blue Light for Higher Cannabinoids
Some growers have discovered a strange spectral trick to get higher terpene and cannabinoid levels. It goes against the natural seasonal light shift, but it can increase terpenes by a reported 50%.
At the end of flowering, in the final 3-7 days, growers return to a spectrum with lots of blue light. Sometimes, they switch bulbs from HPS back to MH (if their ballasts are compatible). Or — if they’re running tunable LEDs — they can simply change the settings on their controller.
It’s unclear why the change in the spectrum — which would be unnatural outdoors — produces more terpenes. Some growers think that it’s a stress response because blue light has more energy than other wavelengths. Other growers wonder if the plants “think” they’re back in the vegetative phase and they push more growth as a response. It’s as though the blue light sparks growth, except the growth, goes into the buds and overall terpene levels instead of foliage.


Has anyone on here tried this?
 

Hippie420

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Nope. You'll be the first. :)

I learned a long time ago not to discount anything 'til I tried it first as far as growing went. So far, everything (flushing/going all dark before harvest, etc.) has been pure cockamamie theories, but ya never know 'til ya try.
 

RosterMan

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Excuse me Ma'am Just one more thing
Sounds like a Rusty Nail story to me
1657026402201.png
 

oldfogey8

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Nope. You'll be the first. :)

I learned a long time ago not to discount anything 'til I tried it first as far as growing went. So far, everything (flushing/going all dark before harvest, etc.) has been pure cockamamie theories, but ya never know 'til ya try.

depending on how things go, i may be growing these Freaks out in my tent anyway so i may be able to try it out though i don't have an LED that i can change wavelengths on. I may have to use my T5 fixture. also, i wont have the benefit of a side by side comparison so it will be purely anectdotal and subjective. add that to the fact that i have not grown a Freak before and my results will be more like todays 'the science' as opposed to actual science... ;)
 

oldfogey8

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Agreed. I haven’t been in full on grow mode(maybe ever) so I am at the mercy of the tools(lousy ones at that) that I have at my disposal. Older LEDs, lousy environmental control, failing mental capacity, minimal space, no known strains(or strandivars) history leaves me to a ‘spray and pray’ situation. I may try to convince my brother to try this out but he is difficult to sway(and he is growing for the first time with a cross that has never been flowered that I am aware of). This may be like rosters ‘rusty nail’…
 

Hippie420

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You also have your method dialed in. Why risk screwing up near-perfection, right? We have seen what massive change results in over the last couple of years…
Yep. If it ain't broke, don't fix it. I fell into that trap early in my growing career. Other than a few tweaks, I use the KISS method. It's just a weed, after all.
 

CrashMagnet

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I've read about doing this, but didn't think I had enough experience to know if it really made a difference. I haven't seen anything quantifying how much is required, though a high blue/green ratio during seedling and veg stages is supposed to reduce stretching.

Amazon sells a couple of all blue grow lights, but they are relatively low power. I was thinking I could get one of the directional bulbs and aim it at just one plant and see if it produces more terpenes than the others.
 

oldfogey8

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I've read about doing this, but didn't think I had enough experience to know if it really made a difference. I haven't seen anything quantifying how much is required, though a high blue/green ratio during seedling and veg stages is supposed to reduce stretching.

Amazon sells a couple of all blue grow lights, but they are relatively low power. I was thinking I could get one of the directional bulbs and aim it at just one plant and see if it produces more terpenes than the others.
I have vegged under ‘blue’ T5 for years and always have had short, stocky plants until I switch to flower. My brother has some LED lights that have a veg/flower switch which from what I can tell just adds a lot more red when switched to ‘flower’. His plants were all short and stocky before he flipped. So my anecdotal experience leads me to believe the ‘blue light during veg’ thing. I would not use low power lights at then end of flower though(or anything Jeff Besos is peddling for that matter). I like terpenes and would take really great tasting smoke over really potent smoke any day of the year so I will pursue this personally. BTW-my Freaks are under 10000 k T5’s right now. 10000 k bulbs are really blue in color and the plants are all pretty stocky( they are short too but that is because they are so young).
 

oldfogey8

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I wonder if this may be why people say UV bulbs a few hrs help trichs too. I wonder if they throw a blue Spectrum
My LED’s have a UV LED in them. I also have done T5 bulbs with UV and have been happy with my results but I have no side by side comparison grows(nor any lab data) so I cannot vouch for UV either way.
 

CrashMagnet

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I have vegged under ‘blue’ T5 for years and always have had short, stocky plants until I switch to flower. My brother has some LED lights that have a veg/flower switch which from what I can tell just adds a lot more red when switched to ‘flower’. His plants were all short and stocky before he flipped. So my anecdotal experience leads me to believe the ‘blue light during veg’ thing. I would not use low power lights at then end of flower though(or anything Jeff Besos is peddling for that matter). I like terpenes and would take really great tasting smoke over really potent smoke any day of the year so I will pursue this personally. BTW-my Freaks are under 10000 k T5’s right now. 10000 k bulbs are really blue in color and the plants are all pretty stocky( they are short too but that is because they are so young).
I was thinking of adding the blue light to the existing lights at the end of flower. If it doesn't improve things, Jeff Besos promises to refund my money and take the light back : )
 
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