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

[Guest]

It starts out with a dull colored, dull looking sprout. As it grows, it maintains the "pea soup" coloration and dark glossy blotches form, often accompanied by a kink in the leaf (shown below)
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As the plant grows, the leaves begin to curl downwards, and maintain the strange morphology.
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The majority are effected. I see these signs in many LED gardens to lesser extent.
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The below photo is color accurate. Notice the dark blotches near the petiole and mid leaf

Notice the glossy nature of the dark patches near the midrib of the below plant.

As the lesser affected plant progresses, the more affected plant continues to curl up and display deficiencies.

The heavily affected plants will continue to curl up and show any and all deficiency from the bottom up until leaf drop and it's inevitable slow death outruns the slow development of new growth, a process which can take several months.

 

[Guest]

What this problem is NOT:

Overwatering
Over fertilization
Cold temperatures
Hot temperatures
Low humidity
High humidity
Toxic gas
Pests
Disease

I have ruled these factors out completely through various rigorous trials.

 

[Guest]

Other characteristics that accompany this disorder:

Pastel purple stems.

Poor root development.

Sporadic intense aroma development/decline cycles.

 

[...CR500AF...]

I have seen my plants turn down there leaf's when i have the light to close, but i have never seen the wrap back around the stem almost by those pics.

That is a new for me i am to keep track of this with you, hopefully somebody will jump in with the answer...

 

[xxPeacePipexx]

I wouldn't rule out underwatering - it's more than likely a combination of under and overwatering together creating a pH and EC fluctuation effecting nutrient uptake. LED lights are not the issue!

 

[DaveBowman]

The only time I've seen anything close to this under LEDs is when my pH was way too high and my plants were too close to the lights. Once I got dialed in under my LEDs I haven't looked back.

 

[packerfan79]

Raise or dim your lights, I'd bet my bottom dollar it's par shock. Leds are powerful.

 

[chilliwilli]

I'm now in the 2. week since switch to qb leds and i got the impression that plants drink less. I switched from dimmed vent to temperatur controll vent so temps are no big difference(set to max 31°c 88f). But still my girls drink less. The soil mix is a year in use and i noticed some slow down in veg(think n is low). After switch i got the yellowing on new growth(looked like fe deficiency) but a cup of kelp/shrimp mix per 90l soil helped to turn most nice green again. Some tops still look very light.

P.s the light got changed from cmh/hps mix to quantumboard with lm301h and cree 660nm

 

[ElGato]

the two plants in the last picture look like they're starving to death, they are saying ...feed me ...feed me

 

[CoconutFarmer]

How many lights they get in umol?

 

[Guest]

I have seen my plants turn down there leaf's when i have the light to close, but i have never seen the wrap back around the stem almost by those pics.

That is a new for me i am to keep track of this with you, hopefully somebody will jump in with the answer...

I see it all over, on reddit etc, people just don't recognize it because it's not severe. It's always written off as drooping, not downward twisting.

 

[Guest]

I wouldn't rule out underwatering - it's more than likely a combination of under and overwatering together creating a pH and EC fluctuation effecting nutrient uptake. LED lights are not the issue!

I have plants right now with the problem and the top of the peat is moist, has been for 2 days. They completely stop drinking when they stop growing.

I think lots of experienced growers agree plants look different under LEDs, I'm not going to trade mine in, but they are definitely related to the problem. All the auto flower growers call it "tight internodal spacing" and agree that banana canoe leaves are normal, but their plants are yielding for shit. The plants that make it in my garden never stretch out, and yield for shit.

 

[Guest]

The only time I've seen anything close to this under LEDs is when my pH was way too high and my plants were too close to the lights. Once I got dialed in under my LEDs I haven't looked back.

Ph is around 7, lights are 24" and dimmed to roughly 80%. Leaf IR temps never get above 81 or below 77

 

[Guest]

Raise or dim your lights, I'd bet my bottom dollar it's par shock. Leds are powerful.

What's a good way to measure? Is there an android app? I've heard something about light meters being inaccurate for Led. Lux, par, umol, I don't know anything about this stuff.

 

[Guest]

I'm now in the 2. week since switch to qb leds and i got the impression that plants drink less.

P.s the light got changed from cmh/hps mix to quantumboard with lm301h and cree 660nm

I'm under the Samsung diodes also. What are your roots like? Mine definitely don't drink much, I assume it's because the roots are all fine hairs, zero thick roots

 

[Guest]

the two plants in the last picture look like they're starving to death, they are saying ...feed me ...feed me

The roots won't extend into the soil, I used liquid ferts on a few and got nitrogen tox real quick at low doses, but still no substantial growth.

A lot of the plants completely lose the curly pale look but never grow roots bigger than a yogurt cup, and only respond to liquid ferts by clawing.

 

[q3corn]

I've seen this in my grows many times. I've used a huge range of LEDs from cheap screw-ins to cobs to QBs. I always chalked it up to ph issues or root rot of sorts, and repotting almost always fixed it.

Edit: also too much light was a factor as well. Turning down the lights was key. I fucked up a lot of plants with my VERO cob light because I just couldn't under any circumstances have the light at 100% power.

 

[chilliwilli]

Buttholocaust i can't see my roots because i grow in 90l pots with no drainage hole. The one u use to mix cement in them.

 

[Guest]

Have you tried yelling at them?


No seriously, have you




Tried upping the calcium
and how is your ph doing

I've ran ph from 5.5 to 7, with 5.5 I thought phosphorus was the issue because the seedlings had purple showing on the first set, but right now I have some showing purple on the new growth at 7ph (purple leaves is in their genes but it shouldn't be there that early).

I've been trying to find a good calcium source so I could rule it out. Plenty of calcium in the soil but the roots won't reach out and grab it. Guess I could get some Cal-mag then go from there?

 

[ElGato]

The roots won't extend into the soil, I used liquid ferts on a few and got nitrogen tox real quick at low doses, but still no substantial growth.

A lot of the plants completely lose the curly pale look but never grow roots bigger than a yogurt cup, and only respond to liquid ferts by clawing.

how many full Crops do you have under your belt?