Growing with a Vegetative Stage light for vegetation only...

[postnothrills]

I'm wondering.... when you look at all recommended LED coverage, you always see more space covered by a light during vegetation.

If I was growing with 400w with 60% of that light being in the 660-630nm range, could I veg with a light that had 80% 440nm-470nm...maybe 10% 630nm and 10% IR/Cool White at only 200w while keeping the light closer to the plants than with full cycle lights?

I've read in a few places that plants require less intense light and more light absorption from the 420-480nm range.

 

[bombasticson]

I dont know what your tlkin bout man I would help if i knew

 

[postnothrills]

During Veg, instead of growing with a 400w Full Cycle LED that has about 60% 660-630nm and 20% 470-430nm, and the other 20% in the deep blue/deep red/IR, wouldn't I be able to achieve a more productive veg under 200w of a light spitting out 70% or 80% of f 480-430nm wavelengths? Meaning in a certain amount of space, I could benefit more from a dialed in light of less wattage than a full cycle at a higher wattage.

 

[jubiare]

if your light is 60% reds and the rest blues, that's to be considered already a veg light.. any more than that and you are likely to stunt the plants + issues.

But your thought about less power required for vegging is very correct, thus LED's is easily the best solution within all the light options, proven. (vegging)

 

[postnothrills]

I'm sorry, I mixed up my numbers.......

Full Cycles (most LED panels) run at about 75% Reds (not 60%, don't know where that came from).... and blue's can make up anywhere from 15% to 20%, with the rest being IR/UV/White or supplemental.
So at 400w (real watts drawn), lets say max. is 20% blue. That is 80 watts of blue light.

But lets say you have a LED specifically made for Vegging, and it was 200w with70% to 80% blue. That would be 140w to 160w of blues, with the rest filling between reds, ir, and possibly some cool white. So, theoretically, if you were to traditionally grow 400w throughout a grow, if you had a light made specific to vegging, you could get away with half of the wattage to cover that same area and possibly do better.

 

[postnothrills]

Something like a 65% Blue, 25% red, and 10% supplemental (deep blue-uv/deep red-ir/cool white) at half the wattage of what you plan to use in flower,while kept closer to the plant, would give you super tight node spacing.

Keep in mind this is for the small tent scrog grower.

 

[bombasticson]

Oh now I understand what your talking about... Leds in my opinion are to much money you should stick with hid because you need like 3 leds to get the same coverage as 1 400 or 600 watt hid, but leds do make some dense buds.

 

[postnothrills]

Like I said, this is for smaller grows in 3x3 tents. And, I'm making these custom factory direct so the price isn't too bad. The money spent on keeping heat and humidity down will offset the costs. I only need one small inline fan to get air from outside, and out to the carbon filter.

Anyways, so research has led me to a ratio of 7:1:1 (7 Blue/1 Red/1 White or Supplemental) for a LED Veg light.

 

[bombasticson]

that sounds good for vegetative growth are going to do this with 1 200watt LED?

 

[postnothrills]

Yes.

Each tent is 3x3 with 2 plants growing under scrog. So that is roughly 22w per sqft even though many have said that is not a good way to measure light. And then in flower, I'm using 200w of a Full Cycle mixture, and then a 200w light of Flower specific with an 8:1:1 ratio of Red/Blue/IR.... The IR will be on both full cycle and flower light will be on 24/hr. It will be like a total of 21w maybe. And then there will be T5 lights (roughly 30w to 40w total) made for tanning or reptiles. I need to be in the 280-310nm range where true UVB is. The presence of UVB produces more trichomes and a higher THC content.... I'm going for quantity and quality. That is the joy of mankind and science.... we get to tweak mother natures design a little.

The only thing I need to figure out is the fixture. I have found 3 of the major factories in China that make lights for a few of the companies we hold regard to. There are bar type panels, rectangle panels that we are more familiar with, and then there are square panels. I could spread the light to 2 100w fixtures but I probably wont. Seems unneccesary.

 

[jubiare]

But lets say you have a LED specifically made for Vegging, and it was 200w with70% to 80% blue.

I understand your theory, can't blame you for that; it comes from what you see around in commercial panels and veg mode panels etc.

But as a matter of fact, 80% blue will stunt your grow to say the least.. wont produce you more foliage at all..

what you want is 30% blue max, no needs for more

 

[postnothrills]

30% blue max...for vegging. And how much blue do you suppose I need during flowering?

 

[jubiare]

Around 10 % would do, especially if you plan on employing an other 10% of wider spectrum whites and/or green, IR things like that...

think of when you veg with blueish whites and you add a reddish white and the plants do better... blues is really important but no need to overdo ...

 

[jubiare]

check this out

http://biology.mcgill.ca/Phytotron/LightWkshp1994/1.4 Prikupets/Prikupets text.htm

 

[postnothrills]

This is a REALLY REALLY good read.... although it puts plants through the full growth of one particular light, instead of trying different spectras of light through different phases of the plant, its interesting to see what specrtras produce the most.

 

[postnothrills]

I'd like to hear more opinions on a heavier blue veg light

 

[heuheuheu]

I just got the Blackstar 240 HO. It's a veg only light as I understand it. I don't know the ratio but it looks like it's ~40% red. I'm running into some issues with nodes being stacked too closely. I have 5 or 6 leaves pancaked on top of each other and I feel like I would be getting more light if it was stretching more. My grow box is also too cold since turning off my MH and is slowing growth. This may sound sarcastic but I'm being genuine.

 

[postnothrills]

I just got done reading some posts by Weezard over at the cannabis forum and dude def knows his stuff with LEDs and has the grows to prove it. He recommends 3:1 red to blue veg and 5:1 red to blue flower

 

[jubiare]

I just got the Blackstar 240 HO. It's a veg only light as I understand it. I don't know the ratio but it looks like it's ~40% red. I'm running into some issues with nodes being stacked too closely. I have 5 or 6 leaves pancaked on top of each other and I feel like I would be getting more light if it was stretching more. My grow box is also too cold since turning off my MH and is slowing growth. This may sound sarcastic but I'm being genuine.

that's what I meant. We don't want stunt grow or internodes so stacked together. Blue prevent stretching and you need little to accomplish that, blue helps with flowering and resin production but you want even littler.

As a quick fix, both for temps and stacked nodes, add some 2700k cfl's

 

[jubiare]

5:1 red to blue flower

That's still slightly high, but it won't hurt (mind the budding power of red is the one that puts on the weight, so if you sacrifice some reds for some blues you'll weight some less in the end)