Best color temp for veg?

JimmyIndica

Well-Known Member
~42 watts. Unfortunately no, I didn't run them separately. I've only run the 4000k on it's own. I may have to give it a run. I have run them 2:1(in both combinations) over tomatoes and herbs. Stretching actually wasn't much of an issue, however it caused plants like basil and spinach to bolt. I removed the 2700k emitters and bolting doesn't seem to be an issue anymore.

They've been collecting dust since then. I only bought them cause I though I needed 'moar red' :P. They're pretty inefficient.

4000k emitters gives me very similar results to metal halide.
Good info here!
 

JimmyIndica

Well-Known Member
I'm beginning to believe the "more red" that's needed isn't something we can get in white LEDs... at least not in the amounts needed for the Emerson effect to function.

All the runs I've done at 3350K (2:1 mix of 3000/4000) stretch stops very early in flower.

I've completed one run at 3000K, had massive stretch... however I only got the lamp done after vegging under T5 tubes and going about 2 weeks into flower. I hypothesize that the switch in light had something to do with it. I'm on my second run with 3000K and just going into week 5 it looks like the stretch is similar to the results I've had with 3350K, minimal.

I'd be curious to know if anyone has vegged with both 3000 and 4000. In the case of both my lamps operating at sub 4000K temps the veg has been "bushy" with plants typically showing as much lateral growth as vertical, very thick and leafy. I'm not sold on the +4000K veg yet. I do like the idea of higher efficacy with the higher color temps, but there doesn't seem to be a meaningful variation between the various temps in that regard, at least with Vero.

I just checked and it's the same with CXBs, though there is a 70 CRI option that opens up with the 4000K temp that does have higher efficacy.
Hey rahz what u think causes all that stretch?from the 3k
 

Doer

Well-Known Member
I wish someone else but me would show a pic of what they are calling massive stretching.

I really am confused as to what you mean. Are you growing Indica?
 

Doer

Well-Known Member
Marketing hype sure maybe. But then why is it perceived that swapping back to mh at the end of flower ups trich production compared to hps (benefit of heavier blue) and this seems to hold true harnessing blues in leds whether it be monos cooler temp or just the nice fuller spectrum of leds in general. Greengenes side by side brings legitimate results to this concept. Same stands for cmh, are those marketing hype or a tech fit to replace the standard hps for certain needs if not all of them (different color temps)

I can see someone vegging under hps but I'd like to see the difference in end results given the difference in node spacing before flower. Side by side. I guess if you're trying to fill a space FASTER to maximize the space and TIME if you are in the business aspect and need a certain amount of turnovers every so often. But you can just as well maximize the space with tighter growth using mh if time is not a problem. And honestly it may be worth the extra time in production at the end of it all. Idk. Never done the side by side myself.
Just babble. Sorry. Market babble. I have written this peusdo-science rattle myself when I was try to sell something.


why is it perceived that swapping back to mh at the end of flower ups trich production

this seems to hold true harnessing blues

just the nice fuller spectrum of leds in general.

legitimate results to this concept.

certain needs if not all of them (different color temps)

if you are in the business aspect and need a certain amount of turnovers every so often.
(who does not need space? Time is value, not money)

And honestly it may be worth the extra time in production at the end of it all. Idk.

Never done the side by side myself.

Do you even listen to this drivel as you type it? You and whats his name are an embarrassment. You should be ashamed. This is exactly the bullshit I am talking about.

HYPE
 

bicit

Well-Known Member
70cri, 4000k cree's are listed in the datasheet, but they were never 'available'... still aren't which is pretty frustrating.

Patiently waiting for someone to stock 4000k 2530's....
 

Rahz

Well-Known Member
Hey rahz what u think causes all that stretch?from the 3k
As I explained, in that case I'm not sure it was simply the spectrum. I didn't install the light until week 2 of flower. Stretch continued into week 5. I had to remove the filter from the tent, then the fan. Total of 4 feet of growth above the screen. However, I've grown the same strain from the same mother in my other space w 3350K and got no stretch... total of less than 1 foot above the screen. In fact, under that 3350K I've got no stretch through multiple strains. I'm currently flowering a sativa dominant under the 3000K and total height will be about a foot above the screen.

One thing I should mention is that I'm not growing with weak lights. Both lamps are about 950 PPFD, so perhaps that's relevant.

So, I can't speak for growing under 2700K but I'm not really sure stretch is a concern for any of the other white color temps. In a practical sense I'm not sure there's a meaningful difference between them for veg either.
 

AquariusPanta

Well-Known Member
Great information here, Rahz.

Four feet of growth?! Was that after switching to 12/12?

I experienced similar growth spurts (~2" per day for two weeks) while using x2 Vero 18s, each 30W, a flowering BlackStar, which gave around 100W, and a couple of 3W 730nm stars.

She went from around a foot tall to about four feet by week six
 

Rahz

Well-Known Member
What happened is that I didn't get the lamp finished when I hoped to. I vegged under a 400w CFL panel and flipped the switch and began to flower under CFL. About 2 weeks later I subbed in the LED. I don't know if switching lights at that point contributed to the stretch. I do know that I had stretch problems with the CFL.

The expectation would be that switching in the LED would slow stretch but it didn't happen. I can't really explain it.

I still need to get a few grows under my belt with the 3000K, however I can say with no doubt that the 3350K lamp has no stretch problems whatsoever. Further, it produces stout bushy plants during veg. That lamp is 8 Vero 18s 4000K and 15 Vero 18s 3000K.

I haven't flowered a 100% sativa yet, but there aren't many of those floating around anyway. All the sativa dominants have done just fine.
 

REALSTYLES

Well-Known Member
What happened is that I didn't get the lamp finished when I hoped to. I vegged under a 400w CFL panel and flipped the switch and began to flower under CFL. About 2 weeks later I subbed in the LED. I don't know if switching lights at that point contributed to the stretch. I do know that I had stretch problems with the CFL.

The expectation would be that switching in the LED would slow stretch but it didn't happen. I can't really explain it.

I still need to get a few grows under my belt with the 3000K, however I can say with no doubt that the 3350K lamp has no stretch problems whatsoever. Further, it produces stout bushy plants during veg. That lamp is 8 Vero 18s 4000K and 15 Vero 18s 3000K.

I haven't flowered a 100% sativa yet, but there aren't many of those floating around anyway. All the sativa dominants have done just fine.
I wish I had a stretch problem this is a Skywalker cross that I bred

SAM_0391.JPG
 

Doer

Well-Known Member
I wish I had a stretch problem this is a Skywalker cross that I bred

View attachment 3407484
Yeah, they want to go everywhere but up.

You used that special, no stretch, secret light frequency, with the fantastic, no stretch newwwwwwts. You used no stretch, wonder soil, and your astrologer told you when it was absolutely auspicious for no stretch. Plus, your crystal pyramid has no stretch, properties.
 

OneHitDone

Well-Known Member
I guess this is veg related cause you have to do this first in many cases - What's the best color temp for rooting cuttings?
 

bicit

Well-Known Member
I guess this is veg related cause you have to do this first in many cases - What's the best color temp for rooting cuttings?
I don't think there is an established 'best' but I've had very good results from a 7w 4kK vero 10
 
Top