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Manipulating Short Day Length Flowering Using Narrow Band LED Lighting?

Douglas.Curtis

Autistic Diplomat in Training
I'm unable to find a story I read on chrysanthemum flowers being force into flowering, during full day length (vegetative) lighting. The method used specific wavelengths of LED lighting (blue was mentioned?) along with different timing than the main lights. I don't suppose anyone is familiar with this? (Edit: Found it! LINK)

I understand cannabis is not a chrysanthemum. Still, could there possibly be a specific wavelength, or combination of wavelengths and times, which can trigger full flowering of cannabis under 18/6 lighting?
 

Douglas.Curtis

Autistic Diplomat in Training
I'm still looking for the article. The difficulty is it was only referenced to as a side mention. I'm unable to remember the original topic I was researching when I stumbled across it. I do remember the research labs were full LED, without any HID lighting.


Could it be possible, the cannabis plant has only one or a few spectrums which control flowering? Would you need LED panels which have the necessary wavelengths for flowering available with separate control? Essentially non-flowering related spectrum available 18hrs a day, with flowering spectrum wavelengths only available for 12?


This would definitely have a huge impact.
 

heatherlonglee

Active member
LED 250-VFS GROW LIGHT SYSTEM
Sunset Spectrum
eyehortilux.com/grow-light-systems/led-250-vfs-grow-light-system/

EyeHortilux new LED system thingy coming out. It's going to be crazy expensive for what you get in LED power. This fits the description you requested about blues and reds, manipulated flowering. Hortilux has another LED bar system (water proof) full spectrum (no Sunset Spectrum) with far red in the mix coming out soon also. These LED system's and that CMHPS light with all that far red, got me wondering about red for sure.

On a side note I was quite shocked to see that these LED panels in the grow systems from Hortilux look similar to the newer Quantum Boards. I really have no idea what I'm looking at technical wise.
 

djonkoman

Active member
Veteran
probably farred.
don't know the specific story you're talking about, but the way a plant sees dark/light ois with a compound(phytochrome) that changes form based on red/farred light ratio. so a higher farred will change it into the 'night'-form, higher red into the 'day'-form. and a pulse of the right length at the right time can be used to manipulate flowering despite the wrong lighthours.

(note: I think farred is a term only used in plant-circles, it's not the same as infrared. it's a specific part of the spectrum with 2 boundaries, don't know the exact wavelengths by heart but it's eay to find)
 

Douglas.Curtis

Autistic Diplomat in Training
Chrysanthemums are also phytochrome based, short day length flowering plants. The article mentioned blue light manipulation, while maintaining regular vegetative lighting hours. The result were chrysanthemums flowering during short night periods.


It wasn't farred, there was no mention of red spectrum at all. As far as I can remember, this is relatively new information from 2017.


The eye-hortilux led is interesting, but the price tag is ridiculous. Granted they're lower quality, but I just bought 540w of mixed LED's in 30 & 50 watt cobbs, including built in drivers, in full, neutral and warm spectrums. $27 shipped, some DIY required. Thank you Aliexpress. ;) ($800+ for 250w? PFFFFFFFFT!!!!)
 

BombBudPuffa

Member
Veteran
Chrysanthemums are also phytochrome based, short day length flowering plants. The article mentioned blue light manipulation, while maintaining regular vegetative lighting hours. The result were chrysanthemums flowering during short night periods.


It wasn't farred, there was no mention of red spectrum at all. As far as I can remember, this is relatively new information from 2017.


The eye-hortilux led is interesting, but the price tag is ridiculous. Granted they're lower quality, but I just bought 540w of mixed LED's in 30 & 50 watt cobbs, including built in drivers, in full, neutral and warm spectrums. $27 shipped, some DIY required. Thank you Aliexpress. ;) ($800+ for 250w? PFFFFFFFFT!!!!)
Link?
 

Douglas.Curtis

Autistic Diplomat in Training
This is driving me NUTS!!!
I'm so sure I surfed this page within the last 2 months. I've been going through my browsing history and STILL have not found the page. I will find it, I'm pretty sure it had something to do with growing in shipping containers, with the reference to chrysanthemums being to some other scientist. Female, as I recall. Probably a really smart cookie. ;) I'll keep looking. :D
 

Douglas.Curtis

Autistic Diplomat in Training
OH YEAH!!! :D Knew it was around here somewhere, just took me some time to find it. LINK

https://www.washingtonpost.com/classic-apps/the-cutting-edge-tech-that-will-change-how-we-feed-ourselves/2018/11/06/775ac684-ce66-11e8-a360-85875bac0b1f_story.html?fbclid=IwAR2uijiRA8VHqC6FyKVaFEqlbwFnAyl92MURN5vE_97bX-AT6crXHQtw8wE&noredirect=on&utm_term=.ef2e90b37d4e said:
Given the evolving nature of the technology and its enormous commercial potential, light manufacturers and universities, often in collaboration, are actively involved in research and development.
“We have a completely new era of research,” says Leo Marcelis, a horticulture professor at Wageningen University in the Netherlands. Tweaking light recipes has allowed researchers to manipulate crops in a way never seen before. In the lab, chrysanthemums have been forced into bloom without the traditional practice of curtailing their daily exposure to daylight. This will allow growers to produce bigger plants in flower.


I was correct in my recollection, it's blue light they're manipulating.
“It’s to do with playing around with the blue light at the right moment of the day,” Marcelis says. “Its internal clock is affected differently, so it doesn’t completely recognize it’s still day. There are so many amazing responses of the plant to the light.”
Has anyone come up with anything similar before? I'm sooooo interested in seeing how this translates to the cannabis plant. :D :dance013:
 

Hookahhead

Active member
I'm a researcher by profession. The article that you found made it easier to try and find the information. Unfortunately, it seems that the research about the chrysanthemums and blue LEDs has not been published. I ran Leo Marcelis, the quoted researcher through an academic search engine. He has a few published papers, but nothing relating to this topic. I also tried just "chrysanthemum LED", which returned a lot of results but nothing that seemed applicable to this topic.

The only semi-related interesting thing I was able to dig up was this...

Varietal Differences in Flowering and Plant Growth Under Night-Break Treatment with LEDs in 12 Chrysanthemum Cultivars https://www.jstage.jst.go.jp/article/ecb/53/1/53_17/_pdf/-char/en

The LED-660 + 735nm night-break treatment showed the strongest inhibitory effect on floral differentiation in the 12cultivars. The same effect has been reported for “Iwa nohakusen” (Liao et al., 2014a), and similar results have been reported in “Arajin2” and “Iwa no hakusen” under a combination of 663 and 732-nm light (Hakuzan and Nagayoshi,2013). Thus, the combination of LED lamps with similar wavelengths also exerts an inhibitory effect on floral differentiation.
Basically this is saying that a combination of LED in 660 & 735nm can be used to interrupt the "dark period" thus preventing the plant from flowering. In the above study, the plants were under florescent lamps for a 12h "light period" from 9:00-21:00. The night break treatment was conducted for 6h from 23:00-5:00.

Just a personal hypothesis, maybe dropping all red from the spectrum after 12 hours would allow you to still blast the plant with blue light only, but still trigger the photoperiod response to flower?
 

Douglas.Curtis

Autistic Diplomat in Training
I remember looking for additional information as well and coming up empty. Good find on the article you linked, it's indeed rather close. I believe your theory will be at least partially true as well. What I do know is if this is possible, there's a whole new field to master. ;)
 

f-e

Well-known member
Mentor
Veteran
So leaving the blue lights on didn't effect flowering we think? The plant was effected by just the upper reds though.

If that leaves us looking for a coloured light that doesn't stop flowering, but does plump up buds, I may have something.

I see I have your interest.

A little green light on an ozone generator under a plant, attracted a branch to it. It went unnoticed for some time. This little branch had a terminal bud right against the led that was nothing like the scratch anywhere else. What should of been a bit of air-bud unworthy of trimming, had become a nugget.

One little voice said "well the plant in general was full of flower power, so this little bit didn't matter" but I know you can cover a single branch and it will flower. Flow of chemicals within the plant.. I don't know. I have since then used 100+ green leds (like christmas lights) in a big ball within a plant. It proved green didn't effect flowering, and seemed to have a positive effect. No unexpected nuggets that screamed out at me though. More recent research by others suggests green energy is useful, and if not immediately so, there is a 'pass it on' effect of up-conversion until something useful is made. So I think green light is an energy source that plants can use, and doesn't break the long nights required (it's not a short day plant) for flowering. I can't say that bud developed at night though. Maybe the green was only of use when it was with other colours.

On a different tach, back then I didn't ground my systems. That whole grow was at many thousands of volts. Introduced by the ozone generator at that point. Maybe that was the stimulus that made it outstanding. It's a funny story actually. I'm squinting at a leaf looking for mites one day, when it lifts towards my face, and as it gets to my nose, with me watching all dozeyed. It chucks a lightening bolt at me. Right on the end of my nose! A temporary state of 'wtf' followed, before I figured out that grounding the tank was a good idea.
 

Douglas.Curtis

Autistic Diplomat in Training
The article mentions manipulation of blue light during a specific point in the day.
In the lab, chrysanthemums have been forced into bloom without the traditional practice of curtailing their daily exposure to daylight. This will allow growers to produce bigger plants in flower. “It’s to do with playing around with the blue light at the right moment of the day,” Marcelis says. “Its internal clock is affected differently, so it doesn’t completely recognize it’s still day.

Interesting information on the green lighting experiences you had. I've noticed green light equipment on the market now, for working with cannabis at night. I wouldn't be surprised to see green light "charging" bays, for bathing the plants with green light a few hours before lights on. :)

I wonder if the chrysanthemums flower out normally, or if there are drawbacks.
 

f-e

Well-known member
Mentor
Veteran
I guess red light could be a wake up call, while the dropping blue light levels could insinuate the day is over. It fits around what natural light does. So perhaps they introduce blue light, just so they can turn it off again. The drop in blue illumination being the key.

It's interesting stuff, but it's a day length plant, and iirc ours are not. There was talk of speeding the transition to night with the upper red spectrum once. I was only half listening, but the photochrome ratio change was being rushed along with 730nm perhaps.

I must catch up on the work revolving around the shortest night possible, coupled with the longest day possible. The sum of which, wasn't intended to equal 24 hours.

It's odd how much resistance to green work lighting there has been. The idea was failing a little ~30 years ago, likely because painted incandescent lamps emit far red. That's about when I started making green led torches. Lately head torches have been offered with both white leds, and a red one for hunting at night. Swapped for a high brightness green led, they can be a nice addition to your kit. At under $10 the 10 meter string of 100 green leds should be part of many more peoples setups to. I can't imagine a grow I can't visit because the lights are out.

And drifting back to topic eventually, I will have a go at lighting a plant with just green, and see if it lasts a week. I have a 100 led string spare and it's cutting selection time almost. I can pop a few in a box with the green lights, and see if they do anything compared to the keepers.
 

Dankwolf

Active member
It's a short day plant, just like cannabis.

Can't remember the article but it pretand to plants that flower by photo period (class c I believe). Any way they interrupted. For just a few min every 6 hours with a red 730 nm light and were able to flower under 24 hour light if you count the red 730 nm red light only inturuption every 6 hours .

The study was way more in-depth then I can explain or remember but you get the idea .:tiphat:

I played with 730 nm led's for awhile it improved flowing in a slightly earlier harvest . gave up after a few runs due to the fact oregon is a competive market and simplicity is key to compete .

:tiphat:
 

Douglas.Curtis

Autistic Diplomat in Training
VERY interesting. :) Both the 730nm and the lettuce farm. I can see how the lettuce would be a lot easier, since there isn't a flowering period, but the tech of having 24hr lighting optimized using feedback is awesome. :)

I still believe it's going to have to be all LED lighting, with specific wavelengths not present in the 24hr lighting. Crazy stuff. :D
 
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