unkle_psycho wrote: ↑Fri May 04, 2018 1:53 pm
, because I'm aiming at growing sativa dominant trees. Back in the day when I did SOG with indica dominant clones, I never thought about vegging with my metal halide... it was already perfect.
I'm usually trying to get the optimal grow wether i'm doing indica or sativa, and i prefer to let them express what they are.
Indica are not tall but not small either, with 3000-4000k led spectrum, it's growing with a decent node spacing.
Sativas are tall for sure but imo that's not a reason to change the spectrum. They are just having a longer vegetative stage during flowering initiation. So if i want them to fill in a small space, i'm starting flowering earlier.
What is changing concerning spectrum for me, is that i'm using the growing spectrum a bit longer for sativas, as their vegetative stage is longer during the stretch.
Of course the problem is different when i'm growing in microcabs, but i'm using only indicas in this case.
unkle_psycho wrote: ↑Fri May 04, 2018 1:53 pm
If this plasma taught me one thing, its the certainty that leaf burn is a spectrum issue, not a problem of intensity. I put 2 week old seedlings 30cm under the bulb for 2 days, and no problem.
You are right, in most cases the spectrum is involved in burning-bleaching troubles.
Most people think their HPS are burning leaves becuz it's too hot, but the reality is the hps' spectrum lack of blue and red, the two colors that runs the violaxanthin cycle and control a big part of the photoprotection process. And this lack of photoprotection make their plants burn at "relatively low" light intensity
And concerning the bleaching under led's panels, it's most of the time induced by very high density of light in the uv-blue region (not really burning, it's another kind of stress). Because people don't understant that most led lights produce a fcking huge light density if you are too close from the source