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Varinaut

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For the past 3 years I've had 400 watts of 4000'K Bridgelux LED strips over my 2' x 4', 2-plant hydro system, and have been happy with 1-1.75 lb of quality, dried product per harvest, but, of course, we're always looking for that extra boost in quality or quantity. That said, a couple of shiny biological objects have caught my eye for the past year or so that promise faster/bigger/better harvests, so after educating myself sufficiently on building LED strips, I'm trying to "tune" my light for happier plants.

First, the Emerson Effect. Research has found that while both 660nm and 730nm are photosynthetically active, when exposed to *both* spectra in the right quantities and ratio -- like %5 of total spectrum should be 660nm with a ratio of 3:1 of 660:730 -- the total photosynthetic output is significantly higher than the sum of the output of each of the 2 spectra alone, suggesting a synergistic effect between processes driven by the 2 spectra.

Then there's the effect of 730nm on light-dark transition. Without going into fine detail, as the sun goes down, more and more of the shorter wavelengths are filtered out until, for a brief period just before nightfall, only 730nm and above hit the leaves signaling to the plant that it should transition from its day to night time processes. Without the 730nm photons, the plant takes more than an hour to transition. By illuminating my girls with 6W of 730nm for 6 minutes after lights out, the plant flowers on a 13/11 schedule, and should "finish" a week early.

So, getting the LED parts from Aliexpress, I put together 2 strips to add to my fixture, each with 10x 1W 660nm diodes and 2x 1W 400nm (to control stretch). These are on for the full 13 hours of the grow room "day." I also added 6x 1W 730nm diodes (you can barely see them in the photo in the middle of the strips). The 730s are on from the beginning of lights on and go off 6 minutes after "lights-off."

IMG_20230117_083711017_HDR.jpg

Here's a comparison of the spectra of what I started with, and what I should have now:

4000K-led-spectrum.jpegfullspec-spectum.png.png

The room was put on a 13/11 flowering schedule on 12/15, so we're into week 5 and everything's looking good. Though, the stretch was a bit excessive so I'll probably add 4 more 400nm diodes for the next run. I'll try to update grow progress, but the harvest window is around March 1 so a more complete report then. If any of you have knowledgeable input I'd be interested.
 
The girls are in week 8 of 13/11, and exposed to the "enhanced" spectrum for 2.5 weeks. With a hard target date of March 1 for harvest, they're looking on track, although, the Panama is maturing more slowly and could probably use an extra week; we'll see. The Diet Durban (the near plant) in particular, has some pretty fluffy buds, but with 3.5 weeks to go, I expect them to fatten up nicely. As for the effects of the added spectra, it's too early to say, but if nothing else, the girls *seem* to be maturing more quickly so the EOD 730nm may well be working as advertised, at least in that regard.
IMG_20230205_100011608.jpg
 
Do you have any updates on how your plants liked the change in adding the new leds? I am looking to build a led light myself and would like any feedback you can give.
I want to make one to use on my seedlings and clones that will be about 95% Blue to keep the stretch down and 5% about 4000k.
Then build a light for Veg and Flower. I may try to add a switch so that when I change to Flower I can switch on additional leds in the 660nm to 800nm to help with budding.

Where is the best place to purchase the leds and power supply? Have you used COB leds before? Do they improve the intensity ?

I will be building it for my 5' x 5' x 7' tent
 
Nice grow show! Have you ever read the book “PAD” I think it stands for ( photosynthetic artificial darkness). Its from the 1980 s. I think. Anyway, it is the early research into using leds ( brand new technology) to do what you are doing. At that time leds were cutting edge and we really didnt know what effect they would have on plants. Everything was THEORY. I know some guys tried it but I dont think it ever really did work. From time to time I work on it ( on paper). They had a complex timer system to run certain colors at specific time lengths to effect specific chlorophyll species at any given time. You might enjoy reading it. If you can find it.
 
Good work Varinaut. Its a nice light too, you have done a great job. You should look into a agromax uv florecent tube. You only need about 15-20 watts or probably even less. They put out alot of uvb and uva wich increases the oil and resin production. I dont think they are too expensive either. In your space with how close you get the plants to the led's you could probably get away with a small 8-12watt type. Just thought it might be an idea you want to research and look into
 
Do you have any updates on how your plants liked the change in adding the new leds? I am looking to build a led light myself and would like any feedback you can give.
I want to make one to use on my seedlings and clones that will be about 95% Blue to keep the stretch down and 5% about 4000k.
Then build a light for Veg and Flower. I may try to add a switch so that when I change to Flower I can switch on additional leds in the 660nm to 800nm to help with budding.

Where is the best place to purchase the leds and power supply? Have you used COB leds before? Do they improve the intensity ?
ys
I will be building it for my 5' x 5' x 7' tent

Thanx for the tickle. I'd intended to update this thread back in April, but life.

I'm currently suffering through day 4 of COVID (Thanx!, unvaccinated dumb-asses.) so will be more mentally fit (hopefully) in a couple of days, so let me know how I can help going forward. For the time being, check out Bridgelux EB serices gen3 strips, or, if you want to build custom strips from the beads up, check aliexpress.com where I prefer the Hotred or OTDiode vendors for reliable quality and low price.
 
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Nice grow show! Have you ever read the book “PAD” I think it stands for ( photosynthetic artificial darkness). Its from the 1980 s. I think. Anyway, it is the early research into using leds ( brand new technology) to do what you are doing. At that time leds were cutting edge and we really didnt know what effect they would have on plants. Everything was THEORY. I know some guys tried it but I dont think it ever really did work. From time to time I work on it ( on paper). They had a complex timer system to run certain colors at specific time lengths to effect specific chlorophyll species at any given time. You might enjoy reading it. If you can find it.

Yeah, this is the foundational research on LED spectra and photosyn. Bruce Bugbee (USU) has become the authoritative lighting Guru for cannabis, so most of my decisions are based on his recent research. I did indeed have to add an additional timer to run the far red 6 minutes afer lights out for EOD transition. I do believe, without solid evidence, though, that the EOD 730 nm did shorten overall flowering period by a week or so.
 
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Good work Varinaut. Its a nice light too, you have done a great job. You should look into a agromax uv florecent tube. You only need about 15-20 watts or probably even less. They put out alot of uvb and uva wich increases the oil and resin production. I dont think they are too expensive either. In your space with how close you get the plants to the led's you could probably get away with a small 8-12watt type. Just thought it might be an idea you want to research and look into

It's hard to see, but right down the middle of the light is a 40W reptisun UVA+B tube. Agree that the added UV spectra improves quality of bud, but you probably already know that too much UVB, in either intensity or duration, can be damaging, and stressful to the point of causing plants to hermi. Don't ask how I know ;-/.
 
Yeah, this is the foundational research on LED spectra and photosyn. Bruce Bugbee (USU) has become the authoritative lighting Guru for cannabis, so most of my decisions are based on his recent research. I did indeed have to add an additional timer to run the far red 6 minutes afer lights out for EOD transition. I do believe, without solid evidence, though, that the EOD 730 nm did shorten overall flowering period for a week or so.
Hey man. do you have a book title or website for this Bruce Bugbee? Loking at your setup has made me curious. Thanks
 
Hey man. do you have a book title or website for this Bruce Bugbee? Loking at your setup has made me curious. Thanks

This will give a good first look. Plenty of science based info in his youtube links.:

 
It's hard to see, but right down the middle of the light is a 40W reptisun UVA+B tube. Agree that the added UV spectra improves quality of bud, but you probably already know that too much UVB, in either intensity or duration, can be damaging, and stressful to the point of causing plants to hermi. Don't ask how I know ;-/.
I didnt spot that. Thanks for the reply. Hope you feel better soon man. That covid isnt nice. Interesting tread with some very usefull tips regarding, led lights and your build and how you've documented through you researching how you developed your lighting system further to get better and better results. Anyway get well soon Varinaut, we look forwards to seeing more on the thread.
 
Thanx for the tickle. I'd intended to update this thread back in April, but life.

I'm currently suffering through day 4 of COVID (Thanx!, unvaccinated dumb-asses.) so will be more mentally fit (hopefully) in a couple of days, so let me know how I can help going forward. For the time being, check out Bridgelux EB serices gen3 strips, or, if you want to buicustom strips from the beads up, check aliexpress.com where I prefer the Hotred or OTDiode vendors for reliable quality and low price.

While it’s on my mind, for re: any light you build or invest in, the footprint of your light should be at least the same size as the horizontal area of your entire canopy; i.e. if you grow a scrog, as I obviously do, and the screen for your canopy is 2 x 4, your light should be 2 x 4 with LEDs even across that space but doubled up on the 2 sides (check the bar spacing on my DIY above). With 400W of output during flowering, I measure 40K lumens +- 5K at every point on my canopy, giving me ~1000 PPFD, which is about as many photons as a plant can handle without jacking CO2 and other parameters. Likewise, if you grow xmas trees, your light should evenly cover the max x-sectional area of your plant.

Using more of a point source that doesn’t provide even coverage will concentrate the light to the middle and you’ll loose quite a bit of quantity and quality because the edges will be deprived.
 
Nice grow show! Have you ever read the book “PAD” I think it stands for ( photosynthetic artificial darkness). Its from the 1980 s. I think. Anyway, it is the early research into using leds ( brand new technology) to do what you are doing. At that time leds were cutting edge and we really didnt know what effect they would have on plants. Everything was THEORY. I know some guys tried it but I dont think it ever really did work. From time to time I work on it ( on paper). They had a complex timer system to run certain colors at specific time lengths to effect specific chlorophyll species at any given time. You might enjoy reading it. If you can find it.
Has anyone tried PAD or have any experience with it? Im not trying to “ highjack” this thread, just curious if anyone ever got it to work. I live “ off grid” and I think it would save on my batteries in the winter. It may be a lost cause.
 
Nice grow show! Have you ever read the book “PAD” I think it stands for ( photosynthetic artificial darkness). Its from the 1980 s. I think. Anyway, it is the early research into using leds ( brand new technology) to do what you are doing. At that time leds were cutting edge and we really didnt know what effect they would have on plants. Everything was THEORY. I know some guys tried it but I dont think it ever really did work. From time to time I work on it ( on paper). They had a complex timer system to run certain colors at specific time lengths to effect specific chlorophyll species at any given time. You might enjoy reading it. If you can find it.
That sounds interesting! 💯🔥 I been wanting to learn about light spectrums and nanometers PAR
ECT. But from everything I try to read I guess I'm to dumb to comprehend it. Lol. I have a Mars Hydro TS 3000 and I finally dashed enough money and got it about week 4 of flower and love what the light produced but when I'm started my next grow it was way too powerful so I learned for to take off the drivers and under then after 2 holes one says I/ o and V/O and ever since I've turned them down it's like the plans do not want to grow under them and suck it burns or bends every plant I put underneath it no matter if it's two or three months old it's like it's till it's really bad even if I got them turned all the way down it's not as bad if I got both internally down but if you turn it up at all it started screwing with the leaves I wish I could get it set back to the factory setting at least or had one of those things that measures power your light is putting out. Any help would be much Appreciated! I've asked and tried to research for 4 years now.
 
Yeah, this is the foundational research on LED spectra and photosyn. Bruce Bugbee (USU) has become the authoritative lighting Guru for cannabis, so most of my decisions are based on his recent research. I did indeed have to add an additional timer to run the far red 6 minutes afer lights out for EOD transition. I do believe, without solid evidence, though, that the EOD 730 nm did shorten overall flowering period by a week or so.
Hey man, I know this is an old post but its been in the back of my mind. Bugbee says that he has not seen any evidence of uv light increasing thc levels but I have played with it “ both a reptile lamp and uvb leds” and I am coninced that uv light makes plants a lot more resinous. Maybe not more thc but they definately get frosty. Has anybody else seen this ?
 
Hey man, I know this is an old post but its been in the back of my mind. Bugbee says that he has not seen any evidence of uv light increasing thc levels but I have played with it “ both a reptile lamp and uvb leds” and I am coninced that uv light makes plants a lot more resinous. Maybe not more thc but they definately get frosty. Has anybody else seen this ?
This is just my opinion, I'm not sure but could it be that it increases the size of the trichome heads or increases the terpenes, flavonoids and other cannabinoids content, not just THC?
 
This is just my opinion, I'm not sure but could it be that it increases the size of the trichome heads or increases the terpenes, flavonoids and other cannabinoids content, not just THC?
Could be. 🤷 I seem to remember reading a research paper where the guy proposed that uv light was the energy needed to convert cbg to thc. He gave some kind of example that involved 2 balloons rubbing together or something like that. Sorry, I cant remember shit anymore. lol. If you do a google search you might find it. 🧐
 
Hey man, I know this is an old post but its been in the back of my mind. Bugbee says that he has not seen any evidence of uv light increasing thc levels but I have played with it “ both a reptile lamp and uvb leds” and I am coninced that uv light makes plants a lot more resinous. Maybe not more thc but they definately get frosty. Has anybody else seen this ?

I noted Bubgee's comment that UV doesn't stimulate more cannabinoids, but I've seen firm evidence that it promotes more THCV, which is a cannabinoid I'm particularly interested in, so I plan to continue exposure of my plants to UVA+B during the last 5 weeks of flower. Might be a waste of electricity, but until there's conclusive science to the contrary, I'll continue with the UV.
 
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