First Grow journal - 320W - 3X3 - Organic

[Hyakutak]

My electrical knowledge is limited but If I do have a constant voltage driver, It shouldn't go higher than 48v right? And the series is dividing 48v by 22 right? And if the voltage of the in the serie mono strip is inferior than the maximum voltage of the Cree led, I shouldn't have any problems, no?

A lot of assumptions lol.

[LivingLight]

My electrical knowledge is limited but If I do have a constant voltage driver, It shouldn't go higher than 48v right? And the series is dividing 48v by 22 right? And if the voltage of the in the serie mono strip is inferior than the maximum voltage of the Cree led, I shouldn't have any problems, no?

A lot of assumptions lol.

Oh right you got a CV driver, that's a bit weird for me xD
It is not usual with leds because the leds got a specific voltage. If you force the led at a lower voltage, the current will drop sharply till the voltage drop of the led Vf match the voltage you are applying. That's why we usually are using voltage auto-adjust drivers (CC). So finally, the idea in your case is to try to match the driver voltage, you're right.

So the best is to go for a 48v serie as the one i've simulated with 12x660 and 8x730
You won't get problem because the actual voltage of the strip is probably 48v even if the datasheets says 45v. The driver is forcing the strip Vf, probably adjusting with a higher intensity. If you could get a problem it would be already happening xD

[Hyakutak]

I just followed de led gardener guide who recommended CV driver for this build and hacked the build a little bit to add mono LEDs.

Thank you very much for the spectrum! I'll modify it this Thursday but do you also recommend it for veg? Or only flowering?

[LivingLight]

Thank you very much for the spectrum! I'll modify it this Thursday but do you also recommend it for veg? Or only flowering?

Very good question xD
The answer depends on the way you want your plants to grow.
For now, with your actual spectrum, i think your plants would benefit of more SAS and I'm pretty sure you could obtain better results with only 3500k. I can be wrong but i've tried many times to supplement my veg spectrums with a bunch of 660nm and it always was a mess
But now if i compare the 3500k only with your future flowering spectrum, i think the flowering spectrum would be a bit more stretchy in veg. I think both could be good veg spectrums, but i got a preference for the 3500k for 2 reasons:
-First i prefer to limit the phytochromes HIR in veg because of its effect on the global photosynthetic efficiency, specially with high light intensity.
-Then i think it could be beneficial to get 2 spectrums because i believe that the plant is responsive to the spectral changes. And the switch between a simple 3500k and your futur flowering spectrum represent well the natural spectral changes that induce reproductive stages.

My favorite veg spectrum for now is a 3000k + 450nm supplementation to reach around 3500-4000k
And even if i've often tried to add deep red to many veg spectrums, i've never tried to compensate with far-red for now. So i can't really be sure.

[Hyakutak]

Okay, thank you again for this answer!

What do you mean by "it was a mess"?

My favorite veg spectrum for now is a 3000k + 450nm supplementation to reach around 3500-4000k

During the whole veg or just for starting?

[LivingLight]

What do you mean by "it was a mess"?

The leaves was small, stiff, the plants really dense so it was hard for the light to penetrate the canopy and it was creating high moisture points. The global plants development was slow compared to my usual setup. And the worst part i think, is the leaf behaviour that kinda hide nutrition symptoms with delayed senescence.
It was similar to yours but with all negative points amplified. Sometimes i was messing because of a lack of nutrients i couldn't see clearly. The leaves was falling but still fully green, it was pretty hard for me at this time to understand the fck was happpening xD.
With more SAS, i get really healthy plants and nice yelds, and each time i was trying to add 660nm, it was ridiculously small and unhealthy. For sure i was a bit loud on supplementation, but at least i've seen clearly what could happen with an excess of this colour.

My favorite veg spectrum for now is a 3000k + 450nm supplementation to reach around 3500-4000k

During the whole veg or just for starting?

I'm lowering the blue part during 3 weeks, and finally switch off 1week before flowering.

I like the way you are showing your plants, we can see easily the stiffness and the density . It's still pretty ok for you but i see clearly the negative effect of the low SAS spectrum.

[unkle_psycho]

The ambiguity on far-red, i think got 3 origins:

first the emerson effect, we don't really care a lot about that because its effect is minimal.
Marketing around emerson effect make people lost the first goal of the spectrum optimisation.

second is the ambiguity of phytochromes responses:
a high Pfr/Pr rate delay flowering for sure but that doesn't means we don't have to use red, let me explain.
There are two distinct kind of phytochrome responses. One highly depend on the Pfr/Pr rate, and the other (HIR), less understood, depend more on the global activation. that means you can trigger some phytochromes effect using a lot of red but in the same way, balance the effects it could have on the Pfr/Pr rate using far-red. In a way, that's exactly what the solar spectrum is doing.

Third ambiguity is on the phytochrome diversity of effects on the SAS, the Circadian clock, and the flowering locus..
You'll need to understand all these interactions to use the red and the far-red smartly.

So could I use 730nm in the daytime to delay flowering in autos?

[LivingLight]

The ambiguity on far-red, i think got 3 origins:

first the emerson effect, we don't really care a lot about that because its effect is minimal.
Marketing around emerson effect make people lost the first goal of the spectrum optimisation.

second is the ambiguity of phytochromes responses:
a high Pfr/Pr rate delay flowering for sure but that doesn't means we don't have to use red, let me explain.
There are two distinct kind of phytochrome responses. One highly depend on the Pfr/Pr rate, and the other (HIR), less understood, depend more on the global activation. that means you can trigger some phytochromes effect using a lot of red but in the same way, balance the effects it could have on the Pfr/Pr rate using far-red. In a way, that's exactly what the solar spectrum is doing.

Third ambiguity is on the phytochrome diversity of effects on the SAS, the Circadian clock, and the flowering locus..
You'll need to understand all these interactions to use the red and the far-red smartly.

So could I use 730nm in the daytime to delay flowering in autos?

Actually it's supposed to be the opposite. A high Pfr/Pr rate is obtained with a high red light proportion. It's a bit confusing i know xD
The auto arn't supposed to be photoperiodic but we can assume that the direct effect of phytochromes on the flowering locus remains the same.
a lot of Far red to accelerate flowering
or a lot of red to delay flowering
could work on autos i guess

[unkle_psycho]

Ok, if I got it the wrong way around, that would mean 660nm then? 660 and 730 are the frequencies that handle pfr/pf rates, so they 'fight' each other?

So if I'm using 90cri, does that mean I would need to add even more 660nm to compensate for the far red, compared to 80cri? Or would it be more complicated since the levels of 660 would also vary between 80/90cri?

[LivingLight]

Ok, if I got it the wrong way around, that would mean 660nm then? 660 and 730 are the frequencies that handle pfr/pf rates, so they 'fight' each other?

So if I'm using 90cri, does that mean I would need to add even more 660nm to compensate for the far red, compared to 80cri? Or would it be more complicated since the levels of 660 would also vary between 80/90cri?

660 and 730nm are the most effective radiations on phytochromes and are acting as opposites yes.
the 90CRI warm white usually got lower Pfr/Pr ratio than 80CRI ones, according to my calculations at least. So in order to delay flowering you could add more 660nm deep red.
But be carefull because this kind of white already got a lot of red, that means the High irradiance responses are well triggered already. An excess could lead to enhanced photoprotection and result in a poor photosynthetic efficiency.
The more your light density is high, the more you got to be carefull.