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Can we solve the mystery LED deficiency before it takes over the world?

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I Care

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The condition that started this thread was too little light and they admit running below full power and also hanging the light two feet away from the plant. I experienced the OP issue, fought between full spectrum LED and fluorescent tube lights until eventually heard Bugbee say too much light is basically impossible in cannabis from start to finish.

Nice thread Here,.....old one but i will give it a shot.
Did anybody come Up with a solution?

I have the Same Problem.
I am Not unexperienced,planted my First seeds over 30 years ago. Ran some nice big crops.....Always HID......the Last one was mixed.a few 1000 Watts dimlux Mixed with lumatek Zeus 600 pro,got the lumatek only to keep Temperature down.there was never a problem.now i know because there was the HID in there that saved me i guess.now i grow with Led alone und it is Like i am a total noob.
I believe what the OP said is true.in my grow everything Looks Like Phosphorus deficiency.....blue purple leaves.poor buds.realy poor.red stems. There is a Magnesia Thing going in too.
The plants Look almost black.
You better keep doing exactly what youre doing, but you need to water every other day and keep a good capacity of run of at least a third of your container size so your plants never have to take a break from feeding when the water has transpired. Otherwise you have enviously healthy plants. You can basically flood these plants like crazy when you’re running led. When they stop drinking then you’ve got chop.


Just saying this to express the only thing you really could change if your finding tht after 4 days without water there is excessive salt content. Easiest way to correct this is to do more water more often.
 

LJ farming

Well-known member
I honestly can’t say for sure?

First thing I would do is lower pH to 5.6-5.7

Then check the runoff.

If the pH is higher and the EC is lower it’s not a nutrient problem MOST LIKELY?

How about environment? LEDs need 82-85f and 70% humidity until week 5/6

Lastly getting the plant (rootbound) in small coco pots is imperative if you want to force feed them several times per light cycle?

If running any other media than coco? Discard everything said above!

Peace
 

aCBD

Well-known member
I only know soil and yes i also experienced that plants look bad with low ppfd and they thrived when cranking it up.
Soil base ph around 5.8, add around 1.3gr dolomite per liter soil, light on 50% first week with recommended distance of the manufacturer and then watch what the plant is doing. Too much stretch? Crank it up. Keep canopy temperature above 25°C at least, better aim for 27-29°C and humidity in the mid range and higher. Crank the light intensity up daily and slowly to get a feel. :watchplant:
Growing with LED to me is like running a marathon but with HPS it felt like a sprinting competition cause the canopy is warmer and the plant just takes up the nutrients like crazy. Canopy temperature is very important imo.
Too cold mixed with too much watering and it looks like a nutrition deficiency.
 
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@Absorber.......usually i grow in Mapito......since that didnt Work Out i switched to Coco in 1 gal pots..... Didnt Work Out either,so transplandet a few in soil .....Just to make Sure......didnt Work Out either ..
Ok,you are talking about 460 ppm.is this the 700 or the 500 scale? Can you Express it in EC for me?
No Clay in the pots......
 

Absorber

Well-known member
@Absorber.......usually i grow in Mapito......since that didnt Work Out i switched to Coco in 1 gal pots..... Didnt Work Out either,so transplandet a few in soil .....Just to make Sure......didnt Work Out either ..
Ok,you are talking about 460 ppm.is this the 700 or the 500 scale? Can you Express it in EC for me?
No Clay in the pots......
0.9 EC roughly, im on the 500 scale
 
0.9 EC roughly, im on the 500 scale
Ah ok.....that really isnt a Lot......my Tap has 0.4 EC......with calmag and Epsom i am at o.6.....that dont leave much space for Base nutes....above Somebody mentioned that i am giving Not enough light ....when i crank Up the ppfd the plants get physicly hurt .....the leaves will Twist,do all Kind of Strange Things and......and the leaves will get Like little bites/holes.,....plants are very Clean.....No Bugs,mites ......i will Provide some Photos later on when i am at the girls
 

Absorber

Well-known member
Ah ok.....that really isnt a Lot......my Tap has 0.4 EC......with calmag and Epsom i am at o.6.....that dont leave much space for Base nutes....above Somebody mentioned that i am giving Not enough light ....when i crank Up the ppfd the plants get physicly hurt .....the leaves will Twist,do all Kind of Strange Things and......and the leaves will get Like little bites/holes.,....plants are very Clean.....No Bugs,mites ......i will Provide some Photos later on when i am at the girls
If your plants arent drinking properly increasing the light probably wont help it will just increase the problem , my water is rain water and is 50PPM .
Because i water with lower PPM and have no medium i water them constantly in my flood and drain ,all automated .
It looks like a DWC but its not
20250124_201410.jpg
 

VerdantGreen

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i haven't read the whole thread but i see this a lot and i would say this problem is too much light. The leaves are curling down to avoid those photons and the plant can't get nutrients quickly enough to keep up with the light it is receiving.
I've used LEDs for 15 years and when i started they were a lot less bright and they were great for veg but a bit weak for flower... These days they are very bright and it is often too much for veg but great for flower.
Thinking in terms of DLI ( Daily Light Interval ) the total amount of light the plant gets in a day) , if you veg at 24 hrs light then that is already twice as much DLI light as 12/12 flowering under the same light intensity... so my advice with LEDs in veg is to have 6-8 hr dark spell for starters. This brings the DLI down most effectively and plants prefer a dark period (providing they are still getting a high enough DLI )
In perfect growing conditions, the plant will handle the intense light better, but if anything 'falls behind' like nutrition or root space of ventilation/temps the plant will fade a lot more quickly when it is getting so much light.
Cal/mag is often one of the first things...
So raise the lights and have a dark period in veg for starters

VG
 
If your plants arent drinking properly increasing the light probably wont help it will just increase the problem , my water is rain water and is 50PPM .
Because i water with lower PPM and have no medium i water them constantly in my flood and drain ,all automated .
It looks like a DWC but its not View attachment 19138830
Your plants Look nice.....especially that lil cremlin there 👍😃
May i ASK what your Background EC is?
Nft is different....No Media where Spikes can Happen.
My ph is proper......of course ph Drops as soon as salt Spikes apear.then ph drops.thats why i counter act with flushing ...but that is Not ideal.
@VerdantGreen ......i Always have my DARK periods......since i live in Germany.....i have to watch the electric bill.i guess everyone knows about Germany and the Inflation WE have . I might give a shot at osmoses water and a very Low EC .......maybe i try o.8......
IT Just Comes to my mind that i was doing some stuff in the tent Yesterday and vorgot to Turn Off the Lights......Hope they Still Standing today
 

VerdantGreen

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@VerdantGreen ......i Always have my DARK periods...
That should help, but the fact remains that your plant cannot 'keep up' with the amount of light it is getting, so maybe you need to improve the environment / nutrition to make it more optimum if that is possible.. or reduce the amount of light. I am a micro grower who grows with LEDs in very low height cabinets and often when i repot a plant (organoc soil) it will only be 'happy ' under the light for maybe a week and as soon as the roots fill the pot and its growing conditions become less than optimum they start to look like yours.

You might be surprised how high EC plants can be happy with under LED if all the other conditions are near perfect

VG
 

LJ farming

Well-known member
IMO if anything looks off at anytime during the growth stages always lower the light stress until you figure out the problem then slowly increase the light/stress until you are damn sure you figured out the problem and everything else is correct and they need more light. Indoors light will always be the limiting factor IMO however it is also incredibly easy to give them too much light anytime from cut to FLIP. then they should be ready for all you got by the end of stretch.

As always just my opinion.

Peace
 

LJ farming

Well-known member
Perhaps don’t run the extraction fan as long to keep the rh higher when the lights are on?

Again I honestly don’t know and every grow room is different.

You can see the history on TrolMaster and it’s all about finding the happy medium I guess?

I use an Apogee to measure the light because TrolMasters ppfd meter is junk.

IMG_1314.jpeg
 

Absorber

Well-known member
Perhaps don’t run the extraction fan as long to keep the rh higher when the lights are on?

Again I honestly don’t know and every grow room is different.

You can see the history on TrolMaster and it’s all about finding the happy medium I guess?

I use an Apogee to measure the light because TrolMasters ppfd meter is junk.

View attachment 19138883
It was a 40°c day i think its doing ok it only takes a couple of minutes for RH to recover so its no biggie
 
Perhaps don’t run the extraction fan as long to keep the rh higher when the lights are on?

Again I honestly don’t know and every grow room is different.

You can see the history on TrolMaster and it’s all about finding the happy medium I guess?

I use an Apogee to measure the light because TrolMasters ppfd meter is junk.

View attachment 19138883
Aint no way i can raise the Temperatur to 85....thats about 29 celcius.....cost me a Fortune 😅....besides you are Supplementing CO2..... My Air goes Out the window.....i need my Appartement Air tight,other vice i have the cops in the House......but my exoust is running on 5 percent......my Temperature is about 25 celcius....rh around 60......vpd Chart says it is OK.......maybe IT really IS the EC levels......i thougt with Led EC levels are supposed to be Higher.....with HID i usually start at 1.4....with Background EC o.4 and Work my way to 1.8 ......but i will give it a shot at lower EC ......who knows ......🤷🏼‍♀️
 

LJ farming

Well-known member
like I said every grow room is different. I pay a fortune to run sealed room. It costs a lot more to control the environment and add CO2 in a sealed grow room. I wouldn’t do it any other way because the quality goes up and the length of a grow cycle goes down more than enough to justify 2-3 times the cost of running a fresh air room. If I was only growing a headie stash I guarantee you it would be a fresh air room!
 

LJ farming

Well-known member
You are better off running HID for the heat factor alone if temperature costs you a fortune. LEDs will not perform well at anything under 28-29c as well as higher rh than HIDs. A lot of the best dope I have smoked and the best growers I know still run HIDs.

LEDs definitely work incredibly better running 28-29c and a higher rh. In a fresh air room it’s easier to control the environment with HIDs. IMO????
 
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