Leggy seedlings with led?
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thisusernameisnottaken
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I didn't overwatering them the soil was not wet or dry.
thisusernameisnottaken
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Working on it I kind of feel ashamed because I thought I was a pro, but I'am just a noob.
Rocket Soul
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Have you considered this being related to normal stretch for start of flower? Its on 12/12 so why not?
When something stretches if diverts much more growth to above ground than below. Id say you have two related problems. Just try with a proper veg cycle.
When something stretches if diverts much more growth to above ground than below. Id say you have two related problems. Just try with a proper veg cycle.
thisusernameisnottaken
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I will try 18/6 300-400 ppfd about 30-35k lux.
amneziaHaze
Well-Known Member
well maybe your dirt or nutes are too powerfull for seedlings have you considered changing?
allsoo keep the light <30cm
watering you say its okej.
how are the temperatures and air circulation?
and why are you for 10 grows doing 12/12 isnt it time after soo many fails to start using 18/6
no matter how much light you have plants will be sexually mature after a month.if you want to save space dont reduce light do some high stress trening. i would reccomend mainlining because that one has the slowest growth rate but perfect space use.
allsoo keep the light <30cm
watering you say its okej.
how are the temperatures and air circulation?
and why are you for 10 grows doing 12/12 isnt it time after soo many fails to start using 18/6
no matter how much light you have plants will be sexually mature after a month.if you want to save space dont reduce light do some high stress trening. i would reccomend mainlining because that one has the slowest growth rate but perfect space use.
thisusernameisnottaken
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How many ppfd lux do you give your seedlings at 18/6?
amneziaHaze
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i use my 300W lamp.lamp is 29cm high and on 25%.Phone app says DLI 23 and 340lumen
5 days later i lowered it to 21cm
https://www.rollitup.org/t/bubba-kush-2-0-vs-white-gorrila-haze.1084022/ this was my first grow with the big lamp
but with 60W it was around 12cm away
5 days later i lowered it to 21cm
https://www.rollitup.org/t/bubba-kush-2-0-vs-white-gorrila-haze.1084022/ this was my first grow with the big lamp
but with 60W it was around 12cm away
Rocket Soul
Well-Known Member
Try 18/6 but lower intensity, its easy to spook young led plants. I firmly believe this is a cycle issue and not a intensity issue. If you see stretch at low intensity while on 18/6, adjust intensity upwards. Or add some blue.
Ive seen it soooo many times for plants with problems under leds; people try to solve them by over adjusting; nutes, temps or whatever, or try to do several things at the same time and only create a new problem. Once a plant is light stunted some of them takes ages to get out of it. Proper veg cycle with low intensity, and then adjust upwards based on reading the plant is the way to go here. Its pointless to base your action 100% on numbers given that are based on a different grow/genetics/situation.
thisusernameisnottaken
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Rocket Soul
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That is interesting. Whatever floats your boat. Please document it though.
Our grow is mostly clones, seedlings should be able to stand a bit more.
10k lux - why so little light?
Below is a Lux to PPFD conversion chart. At 10k, your plants are getting 150±µmols.
Re. a white LED vs a blurple - what PAR meter did you use? I ask because Photone (which I recommend only as a last resort in most cases) failed when I tested it with a Kind blurple back in 2021. If you're using a lux meter to read a blurple, it's very hard to get a PPFD value. The lux meter reads the light under the curve in the center. If you're using a blurple, there's just not a lot of photons in the green part of the spectrum from a blurple so it's very unlikely that you'll be able to get a good reading.
Also, even though I spent some time gathering the light data for that table, I didn't find any blurple info. It's a dead technology and vendors back then did their damndest to not talk about PPFD.
The key to plant shape is light color - blue = short and compact and red = lots of growth. The key to crop yield (mass) and crop quality is the amount of photons//DLI.
Also, there's no reason to run 18/6 for seedlings or in veg. Cannabis does not need darkness - it performs the "dark cycle processing" when the lights are on. "dark cycle" is how the second stage of photosynthesis is described. It has nothing to do with the amount of light.
How much light should plants get?
The light values below are typical of my grows (5 autos + 1 photo). There is some similarity between what growlightmeter.com is publishing and the data below up to mid-veg, IIRC.
My approach is simple - get the plants to the light saturation point as quickly as possible. Research has shown an almost linear relationship between crop yield. The paper is "Frontiers in Plant Science…" and you can see that going from 600µmols to 900µmols resulted in a significant increase in yield.
Bugbee has done excellent work on this topic and the paper by Chandra et al is helpful. Chandra discusses an increase in photosynthesis whereas Bugbee talks about crop yield (mass) and crop quality (the ratio of flower to total mass). All good stuff but the bottom line for me has been to get all of the factors of the grow environment squared away, turn the light up, and enjoy the show.
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Rocket Soul
Well-Known Member
Green and blue are antagonists; blue responses (amost them is stretch control) is inhibited by green: blurple has no green so maybe you wont see the same stretch control in a white light as a blurple.
Blue photons tend to produce short, bushy plants while red photon encourage growth. Green doesn't impact plant morphology but it does allow growers to view the grow environment without having to use special glasses. Bugbee discusses this in one of this older videos - it could be in this one. When I started growing again in 2021, I glommed on to his videos because I had a Kind blurple and was wondering what the big deal was with white LED's. I got my answer, and a lot more, from his videos.
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thisusernameisnottaken
Well-Known Member
I am testing with 2 autos almost 7 days old 18/6, the first 5 days they got 30k lux and they stayed short but now they are getting 10 Dli. They are slow but my vpd is bad and they started in flower soil. Also all plants need darkness.
It also had lenses, still have that light from 2012 with the fans sounded like a airplane.
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A DLI of 10 is very low. My 5 day old seedling was at 275µmols for a DLI of 24 (24/0). It started at 200µmols and a few inches which was enough to raise the PPFD to 275.
I've read many dozens sources and don't recall any recommendations < 200µmols for seedlings. Assuming that a grow is reasonably well set up (the other eight parameter of the grow environment) cannabis will grow very happily at 200- 300µmols very soon after germinating.
Bugbee has a lot of videos on YouTube and "DeBacco University" has summarized a lot of Bugbee's research as well as others. DeBacco's stuff runs < 10 minutes so you only get the highlights vs Bugbee explains things. He is a professor, after all ("So he 'professes'?").
I track my light readings daily using my Apogee and all of my grows have used a similar lighting schedule.
Almost completely off topic…
The probe in the photo is part of the AC Infinity Controller 69 and it's hooked up to their small humidifier. Temps and RH have been pretty good here in SoCal so I'm using the tray from my germination kit but didn't need the plastic cover. It just gets in the way, right?
I put it in a net pot last night and this is what it looked like this AM:
Yup. MT.
My grow is in my garage, doors locked. The only thing I can think of is that there must be rats/mice in the garage (no other evidence of vermin) and the little bastard ate my seedling.
The plastic cover "gets in the way" for a reason!
My Kind LED had fans and weighed, what, 25 pounds. The PPFD map (2' x 4') is below. Best technology 2015 could buy!
No thanks…
thisusernameisnottaken
Well-Known Member
So what ppfd/dli/lux do you recommend for first week cob 3500k 18/6? When I searched for seedlings 18/6 10 dli is enough.A DLI of 10 is very low. My 5 day old seedling was at 275µmols for a DLI of 24 (24/0). It started at 200µmols and a few inches which was enough to raise the PPFD to 275.
I've read many dozens sources and don't recall any recommendations < 200µmols for seedlings. Assuming that a grow is reasonably well set up (the other eight parameter of the grow environment) cannabis will grow very happily at 200- 300µmols very soon after germinating.
Bugbee has a lot of videos on YouTube and "DeBacco University" has summarized a lot of Bugbee's research as well as others. DeBacco's stuff runs < 10 minutes so you only get the highlights vs Bugbee explains things. He is a professor, after all ("So he 'professes'?").
I track my light readings daily using my Apogee and all of my grows have used a similar lighting schedule.
Almost completely off topic…
The probe in the photo is part of the AC Infinity Controller 69 and it's hooked up to their small humidifier. Temps and RH have been pretty good here in SoCal so I'm using the tray from my germination kit but didn't need the plastic cover. It just gets in the way, right?
View attachment 5337180
View attachment 5337186
I put it in a net pot last night and this is what it looked like this AM:
View attachment 5337187
Yup. MT.
My grow is in my garage, doors locked. The only thing I can think of is that there must be rats/mice in the garage (no other evidence of vermin) and the little bastard ate my seedling.
The plastic cover "gets in the way" for a reason!
My Kind LED had fans and weighed, what, 25 pounds. The PPFD map (2' x 4') is below. Best technology 2015 could buy!
No thanks…
View attachment 5337188
"enough" - no question. Cannabis will grow in as little as 64µmols. You'll get a good drop at modest light levels.
I give my grows a lot of light because there's an almost linear relationship between the amount of light and crop yield and crop quality.
Here's yet another set of light data:
That was an auto grow. And Chris yielded 590gm.
Interesting point - the comment on 6/8/22. Until that time, I was hesitant to "turn it up to 11". I had already done a few grows, had read lots of research and watched enough Bugbee that I could quote him but it wasn't until I watched the DeBacco video that I got my head out of my ass about turning it up to 11.
Later in this grow, I didn't bother to run the lights above 800µmols. Why? There were so many "donkey dick" colas that I couldn't be bothered to take the light readings. I take at least 12 samples when I measure the canopy on a large plant and, by that point, it just wasn't worth it.
Oh, that yield was after thrips romped and stomped through the grow.
Anyway, I've never had a healthy seedling have problems at 200-300 and, once they hit veg I try to ramp it up as quickly as possible.
thisusernameisnottaken
Well-Known Member
Update the problem was that they didn't get enough ppfd/dli/lux.