Aqua Man
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Yeah its like the last piece of the puzzle that kinda puts so many things in order for me.I thought this segment was interesting from the paper:
Cannabis plants grown under blue light with a short photoperiod (12 h light:12 h dark/flowering stage) improved cannabinoid content (Magagnini et al., 2018). This same study suggested that there is a synergy between UV-A and blue wavelengths that induces cannabigerol accumulation in cannabis flowers.
My personal testing bears this out.
And this
A low percentage (≤ 24%) of green light enhanced plant growth, whereas plant growth was inhibited under a higher percentage of green light
I find interesting. Taken together, these 2 studies say that green at high PPFD promotes the highest CO2 consumption, and therefore photosynthesis, however when you supply more than 25% green you actually stunt the plant.
My takeaway is that highest possible photosynthesis is not our goal when growing cannabis, if large cannabinoid rich plants is what you are after.
I wish @Milson was still around, he was always able to cut thru the chaff on these kinds of papers and pull out the nuggets important to us growers.
You mention that HPS>MH above, I think perhaps that generalization does not hold 100%. I run Eye Hortilux bulbs with this spectrum in my non-LED tents, and after more than a dozen grows, I find this bulb / spectrum outperforms all others in terms of size and cannabinoid profiles.
View attachment 1185445
I'm starting to see why that might be. Your original paper also discussed Orange - this bulb has a lot more green and orange than most of the other light sources out there.
so cool.
Whoa wait a sec. Who said green is the best.Samsung do the LM301H-ONE for growing leafy greens. It makes no effort to produce red light. IIRC the lettuce morphology we desire is controlled by the blue ratio's. It's a very different plant.
I have grown under green. The plant lost the plot. It moved to single blades and elongated stems. Red petioles. N deficiency. Reveg looking growth tips.
For us, the answer that green is best, isn't accurate. We can't actually grow with green.
Say what? You telling me lettuce photosynthetic systems are different?IIRC the lettuce morphology we desire is controlled by the blue ratio's. It's a very different plant.
I can see why at a cursory glance this could be the nugget people walk away with, but that is not at all what is being said, it is much more complex than that.For us, the answer that green is best, isn't accurate. We can't actually grow with green.
^^ ThisContrary to that the myth that green light is next to useless is absolute BS.
I'm just gonna call bullshit what it is bullshit. Because I want to be clear about the inaccuracy of this statement for ppm reading this.I have grown under green. The plant lost the plot. It moved to single blades and elongated stems. Red petioles. N deficiency. Reveg looking growth tips.
Again re read my posts.. even before it was stated I said to much green will stunt growth.You are calling my green light diary bullshit because it is bullshit?
What do you base this on. Do you have a green light grow under your belt? can you even point to one?
Your question in post #1 wasn't 'which PART of the spectrum' it was simply which. Though I see what you meant to say, now the thread has turned in that direction.
It's a shame you don't believe what happened. It might help you think on why over 25% green is detrimental. Not just that 25% green would lead to green saturation before red and blue, but that ratio's are also triggers.
I'm out. This isn't making me happy. However for anyone wondering..
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Way late to the game but red is the only spectrum that used used directly to drive the initial hydrolysis that is the basis for photosynthesis. Other wavelengths get absorbed and fluoresced out as lower energy wavelengths (red). Sort of. The reality is that in the membrane bound state, this energy seems to be via direct transfer of electron excitation. If you make some green dragon and shine a blue or UV light at it in a dark room, it will flash red. This is the tuned energy emission for the blue absorption spectrum pigments and the rest of the energy becomes heat. The energy loss as heat in that transference is generally speaking, too high for a green photon to absorb and transfer the proper energy level to split water. If plants could effectively use green light, they'd have all evolved to be nearly black.Ok gonna have a little fun here. I'll even correct my illiterate spell check and fat finger mistakes.
If someone can give me the correct answer and explanation for it.... you will own my signature for a week. You send me the text and I'll copy/paste it to my signature.
Rules as follows:
1. 24hrs from time of post it closes.
2. The signature content must not violate forum rules. I'm sure you guys and gals can come up with something within those boundaries
3. Post your answer and it must contain an explanation on why you think it's correct.
4. Feel free to use the web of lies, phone a friend or ask a stranger.
Ok the trivia question:
With a fully grown plant under a high ppfd such as say 1000ppfd which spectrum of light results in the highest photosynthetic rates.
1. Green
2. Red
3. Blue
Don't forget to include the reason why for your choice.
Oh and I'll just leave this here for all you Einstein's... not taunting or anything.View attachment 1185112
That's what I say!This is under the premise of what we know...But most likely there's spectrum's and more we can't and will never see....
What about CMYK subtractive/RGB additive colors?.....
Where additive can be transparent and subtractive compounds?....
Humans always try to make things simple...Nature is far from simple....
I would think Blue cause its just a growing plant..not flowering....
FOE20
Guys, you are loosing me.That's what I say!
Just imagine the science's most humans don't even know exist.
So, is it really about "color" ?
And what the fuck is color.
You might get a kick out of reading about the Phytochrome System.ok, i love this, and it brings up lots of great reading materials and even more questions...
would a sunset or sunrise do anything beneficial? (sunset/rise would be some gradual turning on/off with varying amounts of different wavelengths)
flipping a switch to on has to be some shock for the plants; but might it also key some hormonal action we dont know much about? or make things better/worse? or not affect (i hate that word, i may not be using it properly at all!) time/growth/yield at all.
i mention this for two reasons, first, a lot of what i read has numerical values that can be used in creating the best fake "day" i can give them (if i had control of the wavelengths). second, the aquarium - i know it makes a difference there. so i am making a leap and guessing it might matter in/with cannabis.
having said that... would it be worth considering a more controllable spectrum? (like the aquarium light)
im thinking i can design and produce (no shit, i are an engineer irl) a controllable LED - somewhat like the Fluval 3.0, but with the cannabis' parameters. as a matter of fact my plan is to use that as a jumping off point. but would it be worth it?
i can run some tests with the Fluval, but it is only 59w - although i have 2. (but that leaves one aquarium with a crap light, the other is a Current USA, so not too bad.)
in the aquarium there is a big difference in what grows great using different sunrises and sunsets.
i think it might be fun... urm, i mean useful to look into this. but would it be worth designing and producing a working model (not so hard, just throw money at it, some way to tear down the fluval and combine with whatever, but all still controllable by color!)? would i be able to do enough with 59w x 2 to see if it makes cents (dollars and...) to keep going and maybe make a 5 "bar" light and design a sink...
anyway, just thinking while i still can.
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