# Does 24hrs light make tight node spacing? Do tight nodes=more yield?



## SCARHOLE (Apr 13, 2010)

Its been my experience that under 24 hrs light (CFL REALY CLOSE) the nodes are super close, but I put some 3week old seedlings in for pre sexing an they double their size in a week?
The fem seeds are the same age an no stretching just unbielievably close leafs (you cant even see the stem lol). 
The regs looked just like the fems tell the 12\12 started so i assume its the dark.
Ive heard that the tight nodes will quadruple the yield but takes longer an requires lots of side lighting. 

Anyone else herd that about tight node spacing?
Is it the light cycle keeping em so close?


----------



## homebrewer (Apr 13, 2010)

Your tight nodes are probably more of a function of spectrum and distance than it is your light cycle. 24 hours of sodium isn't going to give you the same growth pattern, nor will a 400 MH. A 1000MH will give you tighter nodes than a 400MH unless the 400MH is right on top of the plants, then they may be about equal. 

I've always heard that there is a point of diminishing returns with a 24/0 cycle and 20/4 seemed to produce the same results while saving electricity. 

More nodes certainly wont hurt yields but I've found that plant structure (branching and sturdiness) played a big role too. See what works best for your strain and run with it.


----------



## cannatari (Apr 13, 2010)

I am the King of tight node spacing. My first couple of cab grows were made to finish under 2 feet. Ever since then I can't seem to grow them any other way. The pic is of a clone in my hydro garden under a T5 fixture. I believe the combo of flourescent light and hydro is the culprit. I can't seem to grow them any other way so I can't say that the yield is more or less than a tall plant. Light cycle has nothing to do with it in my garden.

This is Big Kahuna. 5-6 nodes, 1 1/2" tall:


----------



## SCARHOLE (Apr 13, 2010)

I got a 2 FT box also so i love the tight nodes at first, but i want to clone my NL an AK48 fems an i would realy like em to stetch out.
If its the spectrum of the cfl bulbs should i add more red to increase the stretch?( I got 150 watt 5000 cfl, one 20 watt 7000, one 45 watt 3000 an a 20 watt 3000 i use at night when cause temps allow).
Im going to start keeping the fems away from the light an giving em a 4 hr dark cycle to see if i can get em to stretch a bit.

Any other ideas , I dont think i can clone a 5 in pant with 7-8 nodes.?


----------



## mochadog70 (Apr 14, 2010)

I have done both 24/24 and 20/24 for quite a while on both and can't tell a single difference. Like one of the other poster said that keep that bulbs right on top of them and that'll be the best. I also like have a dark period so the temps can drop so it's more like mother nature. Plus with this 4 hrs of lights off I added more lights because why not!! But seriously no difference that I have noticed and I have done both for a year each. More light = more nodes = more bud. I have even tried 18/24 and still didn't notice anything different, but I have read a lot of wasted light after 20hrs so I went back to the 20/24.


----------



## SCARHOLE (Apr 18, 2010)

Well i got my first 2 clones going about 4 days ago, they pretty small on the stem side 3/4 inch. 

I had to put some plastic wrap under the leaves to keep em from sitting on the soil, lol 

But they are alive an kicken. 

I will put the momas outdoor soon a keep these indoor in case the outdoor fails.

wooooot


----------



## groove (Apr 25, 2010)

It's all about how close the light was. if u use CFl's, u can place them really close (1inch) then plant wont need to grow up to much. u can experience easily in veg state, even I can. (as a newbie)


----------



## acellular (Jul 17, 2013)

I'm trying 24/0 lights on in veg for the first time and the nodes are insanely tight! When I ran 18/6 they definitely seemed a lot stretchier/leggier. This is with 400w MH. I'm switching to 23/1 today to hopefully get some stretch. If that's not enough i'll switch it to 22/2 or 21/3 so they're not abnormally tight.


----------



## colonuggs (Jul 17, 2013)

no 24 hour doesn't make tight nodes ... a light source close to the plant will do that...plus a indica strain


----------



## legallyflying (Jul 17, 2013)

Ok, I'm going to buck the heard and say that 24 hour light source actually DOES decrease node spacing. However, it's not because of the longer light cycle, it is because the day and night (even if there isn't a night, plants do eventually shift to more transpiration ...that is what homebrew we alluded to(this has been studied and proven) temperature Differential is less.

The lower your temperature diff, the better your node spacing is. This is why I bought an external thermostat for my
Mini split. Then the lights go off, 1 hour later the heater comes on. 

You want compact plants? Yes, you do. Close lights and low diff. That's all you can really do. Well. There is the morning dip technique but a guy running CFL isn't going to have the gear to do that.


----------



## Sativied (Jul 18, 2013)

Although I started out with compact plants (because of preveg CFLs just an inch above plants and 24 hrs light) I had some major stretch last round (under hps), so I've been reading up on ways to keep'm low and well, legallyflying summed it up already, besides keeping the lights close (which includes proper reflector and reflection on walls if any) the key really is the DIF. Makes all the difference.  Then I realized why they stay compact under the CFLs, not (just/primarily) the constant light, but the near constant temp.

Here's another source from a test setup: http://www.hightimes.com/read/optimize-your-growing-environment

I don't use a heater (or A/C), I just switch day and night. I'm on 72-82 instead of 65-82.

  (LST-ed, not entirely fair, just showing off ).


----------



## legallyflying (Jul 18, 2013)

That should make a huge difference...the smaller difference that is.


----------



## Sativied (Jul 18, 2013)

Based on what I read the photoperiodism effect far exceeds the influence of thermoperiodism when using high intensity light such as HPS, but still I wonder, can/does a lower DIF result in a longer transitioning to flowering, basically making it veg longer?


----------



## PurpleBuz (Jul 18, 2013)

cannatari said:


> I am the King of tight node spacing. My first couple of cab grows were made to finish under 2 feet. Ever since then I can't seem to grow them any other way. The pic is of a clone in my hydro garden under a T5 fixture. I believe the combo of flourescent light and hydro is the culprit. I can't seem to grow them any other way so I can't say that the yield is more or less than a tall plant. Light cycle has nothing to do with it in my garden.
> 
> This is Big Kahuna. 5-6 nodes, 1 1/2" tall:


wowzer! cool plant ... but I'm wondering how do you get airflow underneath?>


----------



## Uncle Ben (Jul 19, 2013)

I don't worry about stretching. I'm more concerned with plant health, vigor, etc. so I maintain that a 15F drop in temp from day to night is what plant's are genetically tuned too over millenium. They also need a night rest for best performance. Again, that's what they've been programmed to do.

If you must have short internodes you can start by growing only indicas and use lower P foods as higher P foods induce internode stretch. BUT, here's the science on it all with one trick pony:*
A different, but easier approach to using DIF with similar results is to reduce the greenhouse temperature 5°F-10°F lower than the night temperature for two to three hours at dawn. Called a &#8220;cool morning pulse&#8221;, this technique reduces plant height as much as a negative DIF.*

http://www.greenhousemanagementonline.com/gmpro-0410-preventing-plant-stretch.aspx

How high P foods induce stretch, which is what happens with this bloom food happy community. What really causes stretching:
http://www.gpnmag.com/what-really-causes-stretch

Cannabis forums are not the place to get your info. A quick Google that took me less than a minute got me this scientifically correct info based on facts not feelings and anecdotal evidence.

UB


----------



## Uncle Ben (Jul 19, 2013)

Sativied said:


> Based on what I read the photoperiodism effect far exceeds the influence of thermoperiodism when using high intensity light such as HPS, but still I wonder, can/does a lower DIF result in a longer transitioning to flowering, basically making it veg longer?


No, at least not for me and here's the proof - https://www.rollitup.org/advanced-marijuana-cultivation/9114-spin-out-chemical-root-pruning.html I get a flowering response anywhere from 4 - 8 days, depends on the genetics. That's going immediately from 20/4 to 12/12.

UB


----------



## HeartlandHank (Jul 20, 2013)

Yeah, I seem to get better yields with branchy genetics that often do not have tight node spacing.
When I get a plant with crazy tight compact growth (A few Bubba K and Deep Chunk crosses, others) I don't see very good yields.


----------



## Uncle Ben (Jul 20, 2013)

HeartlandHank said:


> Yeah, I seem to get better yields with branchy genetics that often do not have tight node spacing.
> When I get a plant with crazy tight compact growth (A few Bubba K and Deep Chunk crosses, others) I don't see very good yields.


You hit on a point I was going to make but didn't bother. When are internodes too short? I have had plants where the internodes were too short for my style of growing. Take my avatar for instance. That cola was the densest, heaviest thing I've ever grown. It just kept on piling buds one on top of the other with NO air space such that I had some bud rot. Doesn't really matter, you have to deal with what mama nature hands you and a master gardener will have no problem with her in that regard. 

Caveat - original haze I grew outdoors. If it wasn't for a few applications of bonzi, those 7' plants would have finished at 12'. Stuff is amazing. You can apply it and within days see the reaction.

UB


----------



## Uncle Ben (Jul 20, 2013)

Sativied said:


> ....Then I realized why they stay compact under the CFLs, not (just/primarily) the constant light, but the near constant temp.


What you may not understand is by maintaining a negative DIF you done compromised plant health, vigor, and production. You have to make a choice. We've had this discussion about DIF before. Freaked one guy out haha. Just call me one blasphemy mofo.  Post #1584....read it and weep.

https://www.rollitup.org/advanced-marijuana-cultivation/267989-uncle-bens-gardening-tweeks-pointers-80.html


----------



## bushwickbill (Jul 20, 2013)

Whoa, rad looking plant. Just curious, what is your yield like on that, and what strain is it. I've grown some trans siberian that almost looks like that, only not so flat.



cannatari said:


> I am the King of tight node spacing. My first couple of cab grows were made to finish under 2 feet. Ever since then I can't seem to grow them any other way. The pic is of a clone in my hydro garden under a T5 fixture. I believe the combo of flourescent light and hydro is the culprit. I can't seem to grow them any other way so I can't say that the yield is more or less than a tall plant. Light cycle has nothing to do with it in my garden.
> 
> This is Big Kahuna. 5-6 nodes, 1 1/2" tall:


----------



## Vincent VonBlown (Jul 20, 2013)

I agree the closer you can maintain an ideal temp or 75 degrees the happier you and your plants will be... Cannabis is sensitive to environmental changes, which produces the old saying. Grow ditch weed in Hawaii and it wants to turn good, grow the best weed in a rough environment, and it wants to turn to shit...


----------



## Vincent VonBlown (Jul 20, 2013)

One of the reasons you will see medical dispenceries turning down out door pot is because it is "weathered". One of the components of weathering, is "temperature change/variation"... Ideal conditions, produce the best product... You can create conditions indoors, that most of the time can't be recreated outdoors. It's as simple as that, anybody that has done much of both indoor and outdoor growing, can tell you that much.


----------



## Nizza (Jul 20, 2013)

am i right that more P encourages tighter node spacing whereas less will make more spaced out nodes?


----------



## Sand4x105 (Jul 20, 2013)

Uncle Ben said:


> I don't worry about stretching. I'm more concerned with plant health
> ...
> If you must have short internodes you can start by growing only indicas and *use lower P foods as higher P foods induce internode stretch. *
> UB


2-4-6-8-10....


----------



## Sativied (Jul 20, 2013)

Uncle Ben said:


> What you may not understand is by maintaining a negative DIF you done compromised plant health, vigor, and production. You have to make a choice. We've had this discussion about DIF before. Freaked one guy out haha. Just call me one blasphemy mofo.  Post #1584....read it and weep.


Thanks for pointing out that post and link in it. That near constant temp is during the first 7-10 days in a small preveg box, something I've done 5 runs and if I have compromised plant health, vigor, and production by doing so, it's in practice a negligible or at least unnoticable amount (the only thing that limits my production is the 3x4 feet space I have to flower). Like you said, you have to make a choice, sometimes that choice is between lesser evils. I have limited height available so do have to worry about stretch. That's why this time I also work with a lower DIF in my flower setup during transition (to go low-low, the stretched run has been a good learning experience).

If the guy was working with Celsius I can see why he freaked out: 


Uncle Ben said:


> In general, a 85/70F (32/16C) day/night temp is best for most hybrids for maximum carbo production.


85F = 29C
70F = 21C

That may seem like a small difference for an F user, but 32/16C is 89.6/64.8F, which I assume you agree would be unwise to aim for. 85/70F (29/21C) is "the" range widely used and recommend in Dutch forums. It's what the plants have been acclimatized to, what breeders here use during selection etc, and what I will use again during the flowering period (after sexing) as usual. Might want to (get a mod to) correct the conversion on that one to prevent Celsius folks from freaking out. I for one do point Celsius users to your Pointers thread occasionally and it doesn't make it any easier to convince or at least rethink the rest (like harvesting yellow, speaking of blasphemy).



Uncle Ben said:


> Just call me one blasphemy mofo.


Well, please keep it up man, I got distracted for a while here at RIU by going to TnT and such forums, while I can gain knowledge _and_ still be entertained in AMC  I select and work with subject matter experts and authoritative sources for a living. Finding the reasons why they 'can' disagree is what gives me an edge. Thanks to you and some others who aren't just parroting received wisdom I can apply the same thing to my hobby.


Oh btw, post #1584 but you linked to a page with a comment about Dutch tulips   Probably got more posts per page right? Funny coincidence... You are right about those north western breeders though, Oregon specifically, Old Ed, no need to be mean about it. It's not like we all forgot  I got a dutch grow guide from 1987 that partly comes from the same group. Oldskool outdoor growing. As old as it is, I still occasionally use it to debunk forum-'wisdom'. Oh and you're right about those dutch seeds shops too, I refer to them as tourist/souvenir seeds... some people don't seem to like that much honesty.


----------



## Uncle Ben (Jul 20, 2013)

Nizza said:


> am i right that more P encourages tighter node spacing whereas less will make more spaced out nodes?


Come on. Go back one page, and find my post on this issue.


----------



## Uncle Ben (Jul 20, 2013)

Sativied said:


> That may seem like a small difference for an F user, but 32/16C is 89.6/64.8F, which I assume you agree would be unwise to aim for.


Not at all as long as the 64.8F was when lights were out and at the low of the night. I live in an area where that kind of DIF is the norm most of the spring - fall months. Anything from a 10 to 25F drop in night temp is alright with me.

Regarding the conversion, Celsius X 9/5 + 32= Farenheit conversion. 85/60F = 29/15.6C

UB


----------



## NietzscheKeen (Jul 20, 2013)

Uncle Ben said:


> Am I right that you don't bother to read the thread before posting? Go back one page, and find my post on this issue.


Lol, I think Nizza was getting a second opinion on my post, on another thread, regarding high P and plant stretch; I think he misunderstood slightly. 

Edit: No wait. I didn't know there was a discussion of High P nutrients on this thread as well.


----------



## NietzscheKeen (Jul 20, 2013)

HeartlandHank said:


> Yeah, I seem to get better yields with branchy genetics that often do not have tight node spacing.
> When I get a plant with crazy tight compact growth (A few Bubba K and Deep Chunk crosses, others) I don't see very good yields.


I mean, it makes for better looking "denser" colas when the nodes are closer. I think that is the only benefit one will see from tighter node spacing. I've had good luck with long plants as well; longer node spacing.


----------



## Sativied (Jul 20, 2013)

Note the subtle "aim for". It's not a horrible range but indoors there's no need to simulate the downsides of outdoors just for the sake of.



Uncle Ben said:


> Regarding the conversion, Celsius X 9/5 + 32= Farenheit conversion. 85/*60F* = 29/15.6C


Yeah... I don't think we should argue on how to convert C to F, I ask my computer and she's never wrong. Scroll up and see your quote from your Pointers thread, you said 85/*70F*, not *85/60*. Hence the Celsius max and min values you advice there are both wrong and not what you intended. I should have mentioned those SMEs usually don't like it when I edit their errors out either.  Everybody makes mistakes sometimes


----------



## Uncle Ben (Jul 21, 2013)

NietzscheKeen said:


> I mean, it makes for *better looking* "denser" colas when the nodes are closer.....


Reminds of starting with post #172 - https://www.rollitup.org/advanced-marijuana-cultivation/676034-dont-switch-straight-12-12-a-9.html


----------



## Uncle Ben (Jul 21, 2013)

Sativied said:


> Note the subtle "aim for". It's not a horrible range but indoors there's no need to simulate the downsides of outdoors just for the sake of.
> 
> Yeah... I don't think we should argue on how to convert C to F, I ask my computer and she's never wrong. Scroll up and see your quote from your Pointers thread, you said 85/*70F*, not *85/60*. Hence the Celsius max and min values you advice there are both wrong and not what you intended. I should have mentioned those SMEs usually don't like it when I edit their errors out either.  Everybody makes mistakes sometimes


We're splitting hairs here. I took the black and white out of the discussion with a previous post when I said - "Anything from a 10 to 25F drop in night temp is alright with me."

IOW, negative DIF's suck.  The lower the night temp compared to the day means less food reserves lost to respiration processes at night. There's an economy of scale issue here and a bit of botanical reasoning coming into play - you don't want that night time drop to be so radical that tissue production that normally occurs during night is now negatively affected, reduced.

UB


----------



## NietzscheKeen (Jul 21, 2013)

Uncle Ben said:


> Reminds of starting with post #172 - https://www.rollitup.org/advanced-marijuana-cultivation/676034-dont-switch-straight-12-12-a-9.html


And that raises a question for me. What is the best way to trim and manicure a pure sativa? The only illustrations and descriptions I see are for Indicas and Indica dom hybrids. I harvested my plants recently and they had some very solid bud formation, but there have been a few in the past that were light and airy over the whole plant. I made hash out of it, but would rather trim it. I just don't think it will make peoples mouths water like the Indicas do; I mean, send a kid in a candy shop and is he gonna pick two handfuls of delicious party sized milky ways or a gigantic plain Hershey bar?


----------



## Uncle Ben (Jul 21, 2013)

NietzscheKeen said:


> And that raises a question for me. What is the best way to trim and manicure a pure sativa?
> View attachment 2744602


Nice eye candy, we likes it!

Best way? Lots of patience, small clippers, and a cold beer or J to keep you occupied. I wear a loupe and if the small leaves have trichomes, they stay and that's usually a lot. Yep, sativas are a pain but I never met a sativa I didn't like.


----------



## Clumpyoyster (Aug 11, 2019)

Sativied said:


> Although I started out with compact plants (because of preveg CFLs just an inch above plants and 24 hrs light) I had some major stretch last round (under hps), so I've been reading up on ways to keep'm low and well, legallyflying summed it up already, besides keeping the lights close (which includes proper reflector and reflection on walls if any) the key really is the DIF. Makes all the difference.  Then I realized why they stay compact under the CFLs, not (just/primarily) the constant light, but the near constant temp.
> 
> Here's another source from a test setup: http://www.hightimes.com/read/optimize-your-growing-environment
> 
> ...


ok i need to know where you buy your padded wires for LST. I have been using regular insulated wire for mine which works great but i would like to use those foam padded wires. where can i get them? thanks


----------



## vostok (Aug 11, 2019)

Sativied said:


> Note the subtle "aim for". It's not a horrible range but indoors there's no need to simulate the downsides of outdoors just for the sake of.
> 
> Yeah... I don't think we should argue on how to convert C to F, I ask my computer and she's never wrong. Scroll up and see your quote from your Pointers thread, you said 85/*70F*, not *85/60*. Hence the Celsius max and min values you advice there are both wrong and not what you intended. I should have mentioned those SMEs usually don't like it when I edit their errors out either.  Everybody makes mistakes sometimes


Greets to the cat long time no see?


----------



## ZeeeDoc (Sep 2, 2019)

colonuggs said:


> no 24 hour doesn't make tight nodes ... a light source close to the plant will do that...plus a indica strain


I can categorically say that 24/7 produce's shorter plants with tighter nodes, years using this method, it makes the plant more manageable( I do FIM), thicker branches, able to veg for longer which in return gives bigger yields. Having the plant close to the light does prevent stretch however If I grow sativa's it doesn't matter how close I get to the light they still stretch and stretch.


----------



## paraplantastic (Sep 2, 2019)

Aside from spectrum, strain and temp (bordering on stress but not necessarily stress) if a grower is to influence internodal spacing in flower to say reduce stretch, (if so desired) it lies in the day night temp varient. The closer they are to the same the smaller the internodes. Example, 75f day and 70 - 75f night equals tight internodes. The more the variation the longer the internodes. Other factors such as strain, nutes, etc. will dictate how effective -if at all- manipulating the day night temp varient will be. This is what I personally know to be true and I absolutely DO NOT discount any of the prior suggestions regarding this. I hold the opinions of other experienced growers on this site in high regard. Just my 2 cents. If someone has already clarified this then my bad for not reading more closely.


----------



## OG Jewish connissor (Sep 4, 2019)

legallyflying said:


> Ok, I'm going to buck the heard and say that 24 hour light source actually DOES decrease node spacing. However, it's not because of the longer light cycle, it is because the day and night (even if there isn't a night, plants do eventually shift to more transpiration ...that is what homebrew we alluded to(this has been studied and proven) temperature Differential is less.
> 
> The lower your temperature diff, the better your node spacing is. This is why I bought an external thermostat for my
> Mini split. Then the lights go off, 1 hour later the heater comes on.
> ...


any plant that is not adapted to 24hrs for two weeks will do different producing sites. if you change to less 14 most will sex so use that for a fast veg start if 12/12 until finished did this first time with ohio meigs co gold sativas will need longer flower time if only 2 weeks veg they stretch way more now autos best 20-4 then 18-6 no less tried all different growing with 24 seed to bud and so on ogjc


----------



## SchmoeJoe (Sep 6, 2019)

legallyflying said:


> Ok, I'm going to buck the heard and say that 24 hour light source actually DOES decrease node spacing. However, it's not because of the longer light cycle, it is because the day and night (even if there isn't a night, plants do eventually shift to more transpiration ...that is what homebrew we alluded to(this has been studied and proven) temperature Differential is less.
> 
> The lower your temperature diff, the better your node spacing is. This is why I bought an external thermostat for my
> Mini split. Then the lights go off, 1 hour later the heater comes on.
> ...


T-diff is the biggest thing here for sure. It can also be manipulated to control how fast the plants grow and how big they'll end up.
The point of diminishing returns on the veg cycle is 18/6. Anything past that first 18 hours a day is way less efficient.

Low light levels or a lack of blue, or an excess of red, will lead to longer internodes. Shorter internodes will make a higher yield in a given space with a full canopy because you get more points of growth in the same space.


----------



## paraplantastic (Sep 6, 2019)

Combine this with pinching and LST and not letting the center of your plant get clogged up with small shoots and giant fan leaves.... hell yes


----------



## SchmoeJoe (Sep 6, 2019)

paraplantastic said:


> Combine this with pinching and LST and not letting the center of your plant get clogged up with small shoots and giant fan leaves.... hell yes


I like to use a couple of rules for pruning fruit trees. Remove any growth growing towards the inside of the plant and selectively prune to make sure no branches cross each other. Just those two things combined with topping early can make for some impressive results.


----------



## paraplantastic (Sep 6, 2019)

SchmoeJoe said:


> I like to use a couple of rules for pruning fruit trees. Remove any growth growing towards the inside of the plant and selectively prune to make sure no branches cross each other. Just those two things combined with topping early can make for some impressive results.


You mean ganja fruit trees?


----------



## SchmoeJoe (Sep 6, 2019)

paraplantastic said:


> You mean ganja fruit trees?


No, I mean that it's a standard practice with actual fruit trees that also works really well with weed.

Edit; I see how that first post was confusing. Don't mind me, the combination of the pain from a freshly broken foot and a steady lack of sleep has me missing some things that I normally probably wouldn't.


----------



## CBDbear (Sep 9, 2019)

Here is what I could undestand for the N/D diff temp: basically you disturb (I belive termically) the giberellin hormones build up of the plant and thus keep the internodes spacing tighter.
There is a tecnique called cold dump which instead of completely keep the diff neg or neutral for the lenght of the day you just keep the next to zero diff in the first few hours of the day.

I'm really interested in that so if anybody can give any more pointers it would be great!

It seem somone was implying the more ppf on the canopy the less stretch? I've come across so many other factors in my research for informations! IR, blue vs red ratio, Fr VS r ratio, amount of green spectrum and also temps as someone else was saying leaving! aside fenotype and strains...


----------



## VILEPLUME (Oct 6, 2019)

I’ve tried most light combos and found 18/6 to be the best. The root development especially benefits from some darkness.


----------

