Quantum board, stretch in flower ?

Black Thumb

Well-Known Member
Anyone have any experiences or pics of the stretch with the Quantum boards.

Did you see the normal stretch or did you notice a significant decrease in stretch?
 
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Humple

Well-Known Member
I've vegged under quantum boards at both 3000k and 3500k, and definitely noticed less stretch than under 2100k HPS. Seems about the same as the metal halide I was using, which I believe was around 5000k.
 

CobKits

Well-Known Member
has much more to do with spectrum and light intensity than it does if the chips are on a board or on a cob

im vegging with 3500k 90 cri right now and they stack pretty good. they stretch a bit in early flower but always fill in
 

GroErr

Well-Known Member
has much more to do with spectrum and light intensity than it does if the chips are on a board or on a cob

im vegging with 3500k 90 cri right now and they stack pretty good. they stretch a bit in early flower but always fill in
^^^ this ^^^

While there are other factors affecting stretch, in general one big factor will be the colour (kelvin) difference between your veg and flowering lights. The greater the difference between them, the greater the stretch. So if you're coming from the hps (~2100k) world in flowering, and you were vegging with say 6500k T5's, you would be expecting and getting a big stretch. Then when you move to say 3500k (COBs or QB's) in flowering and leave your T5 6500k for vegging, you'll get less stretch. If you changed your veg lights to lower kelvin like say 4000k or vegged and flowered with the same lights (3500k) you'd see the least stretch.
 

CobKits

Well-Known Member
i know a lot of people that only veg with the same lights they flower with. maybe superstiion but theres prob some experience there as well. ive seen plenty of stocky plants vegged under hps
 

Budies 101

Well-Known Member
I use my own PCB build for lights but I don't notice any "extra' stretch occurring... All I see is the future of growing. Save your self money and don't buy the same thing twice, why buy HPS only to replace it later with something else that does the same job.

It's strange because after doing 2 different led builds (cob and PCB) I feel like there is no room for debate on led vs hps... Led is growing with near half the watts as HPS and the PCB builds I have feel like they do better than CoBs because the plant simply gets more of the light, almost no shadows, it's weird. Growing the same as HPS with half the watts and people are still pretending there is a debate as to what light is "better" is a joke. High end LED done right is right at 2x as good as HPS, meaning HPS for watts consumed does HALF the job LED is doing but you have to also accept near no versatility with HPS vs LED builds.

We are not debating if LED are better than HPS we are debating how much better they are than HPS (40%) better on average seems to the case.

Even if there were some small tiny amount of extra stretch in flower using QB's, take the 40-50% less watts for equal growth with an extra inch of hight sounds like an amazing trade off.. I mean, you also gain actual feet of ceiling height to work with when you use QB's vs HPS. Basically if there is stretch you can afford with LED easily... But there is not any extra stretch =)
 

goofy81

Well-Known Member
You should read up on plant negative/positive DIF you help you try to control your stretch.
Especially during the first 2 weeks of 12/12
 

Humple

Well-Known Member
i know a lot of people that only veg with the same lights they flower with. maybe superstiion but theres prob some experience there as well. ive seen plenty of stocky plants vegged under hps
That's the way I was headed, even before I went LED. But now that I've completely replaced my HID gear, I'll be vegging and flowering in three different spaces. I've got a (DIY) grow cab with two 19"x23"x48" chambers: I have a QB288 in each chamber (HLG's 135w kit; it pulls 150 at the wall when I crank it), one 3000k and one 3500k. I plan to alternate between vegging (sometimes moving the plants to my tent, under my 4xQB120 @ 3000k) and flowering in each space, depending on where certain plants are in their cycle. Also thinking of getting another, single QB120 @ 4000k to replace the two 65w (actual) CFLs I use in my seedling/clone chamber. Basically, I'm trying to get my hands on a wide spectrum of spectrums so I can really learn how the plants respond to each. No reason to limit one's self!
 

CobKits

Well-Known Member
replace those cfls with ANY led, even the store bought bulbs (common in 5000k and 2700k)

cfl is the worst for efficiency
 

waynejohn

Active Member
Basically it's a difference between night and day temps...the bigger the difference the more your plants will stretch...if you want to slow down stretch keep the temp as close as possible between night and day or lower them as much as you can for the first 3 hours when your lights turn on
 

Prawn Connery

Well-Known Member
I'm coming from the HID world, so take this for what it's worth. These are the factors that most affect stretch in my experience:

1. Genetics - single biggest determiner. If you don't have head room, don't grow lanky, 12-week sativas. nuff said
2. Light intensity - doesn't matter what light you use, if lighting is inadequate, plants will stretch towards them in both veg and early flower.
3. Heat - the hotter it is, the more they will stretch in early flower as a stress response.
4. Spectrum - it's well known that far red induces stretch and that blue keeps internodes tighter. I've flowered under MH and HPS and the results speak for themselves - less stretch and more compact nodes under MH (blue/green) comparing watt-for-watt to HPS (red/yellow). However, you still need that light intensity.

The kicker is that HPS always outproduced MH in flower due to two factors: HPS is more efficient than MH (more light per watt), and has more red spectrum. Full spectrum CMH reportedly has the best of both worlds, but I've not tested it again HPS. I like that CMH has a bit of UVA/B in it, but don't buy the 315wCMH > 600w HPS hype.

I suspect redder LED spectrums will always outperform bluer spectrums, and having spoken to a few people, that seems to be the case. So I've just bought some 5000K strips to play with in veg, but when I move on to flowering, I'll be looking at something in the 2700K range to emulate my old MH veg/HPS flower set-up.
 

Black Thumb

Well-Known Member
9 -288 boards in a 3x3 at 319 watts.
Week in so far im seeing very little vertical stretch and what seems like bushier lateral growth.
I cant judge the stretch because i took some week old clones in dixie cups without a traditional 1 week veg and stuck them in some 5x5 pots :cuss:
just for testing purposes.

I like that CMH has a bit of UVA/B in it, but don't buy the 315wCMH > 600w HPS hype.
I consistently pull 14- 16 oz per 315 CMH (3100) in 1 gallon bags coco 20 min /day recirc perpetually. I would never switch back to 600w HPS.
 

Humple

Well-Known Member
9 -288 boards in a 3x3 at 319 watts.
Week in so far im seeing very little vertical stretch and what seems like bushier lateral growth.
I cant judge the stretch because i took some week old clones in dixie cups without a traditional 1 week veg and stuck them in some 5x5 pots :cuss:
just for testing purposes.



I consistently pull 14- 16 oz per 315 CMH (3100) in 1 gallon bags coco 20 min /day recirc perpetually. I would never switch back to 600w HPS.
What spectrum are your QBs?
 

Prawn Connery

Well-Known Member
I consistently pull 14- 16 oz per 315 CMH (3100) in 1 gallon bags coco 20 min /day recirc perpetually. I would never switch back to 600w HPS.
I consistently pulled 3-3.5x that (50-56oz) with two 600s in coco. My commercial mates pull 20-24oz in coco per 600. I don't doubt CMH is more efficient (more par watts), but they're no 600hps replacement. Now, two CMH 315s is another story :bigjoint:
 

rocho

Well-Known Member
has much more to do with spectrum and light intensity than it does if the chips are on a board or on a cob

im vegging with 3500k 90 cri right now and they stack pretty good. they stretch a bit in early flower but always fill in
I'm ever more confused!!

Yes, about 5 weeks veg I think. And yes, both 2700/90 and 3000/90 had about 6 inches less stretch in flower compared to the 80 and 70 CRI samples.

https://www.rollitup.org/t/vegging-with-3000k-90cri.936591/#post-13421099
 
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