Adjustable spectrum LED fixtures - turn down red when finishing?

I believe I read somewhere that during the last week of flowering, if you have an adjustable spectrum LED fixture (i.e. SolarSystem 550), that you should turn down the red spectrum a tad to force the finishing to behave differently?

Is that the case and can someone explain the logic behind why?

I'm thinking if that's the case, to set the Blue to 100, the White to 85 and the Red to 70 on a SS550.... Thoughts?

No one has heard of this? I have the controller for my CLW SS550 pair of fixtures but right now I'm using a plain old timer...

Wondering if there's any benefit to the slight cut back in overall power to get this 'finishing' spectrum.

Probably not. You could eventually do two runs and see which one works better.

The idea behind these adjustable spectrums is really to dial in the best response from a given strain that you can grow out many times. There is a general response that plants have to a "base" spectrum, but there are also unique things about each plant that you might be able to tap into over time with adding or subtracting certain colors. Also, if you ever want to grow something other than marijuana under your lights, then you can adjust the spectrum accordingly, as well. Pretty cool idea, imo. A few companies that are exploring these adjustable spectrum lights are: ChilLED, Amare, California Lightworks....and a few others.

If you have a strain that tends to stretch a lot, then you can dial back some of the red. If you want to shorten the internode spacing, then you can dial up the blue...and so on.

But, like I said, you have to do many runs with a given strain in order to determine which spectrum that particular plant responds to the best. It's probably more practical to just go with a less-fancy, full-spectrum white COB fixture or a full-spectrum Quantum Board if you're going to be running a variety of strains each time.

But some of these new lights are just so damn cool and scientific and...well...FUN, I'd like to have them in my grow room just to be the coolest kid on the block with the coolest new toy!

I had red/blue/white dials on my Lumigrows but never really used them. Putting a 5000K COB right over a flowering plant hasn't stopped phenotypical stretching, in my experience.

sanjuan said:

I had red/blue/white dials on my Lumigrows but never really used them. Putting a 5000K COB right over a flowering plant hasn't stopped phenotypical stretching, in my experience.

Click to expand...

Have to say that in my case using about 32 watts of 5000k vero cobs per square foot at aprox 160 lumens per watt..during the 3 first weeks of flowering has reduced the streching of a very tall sativa at least a 30%...