What is wrong with this

[Fish scale]

She is Grown in coco, PH 6.0, The EC is 0.8 and it's coming out in the run off at 0.8 EC so it's coming out exactly the same as it's going in. RH 60 - 65% Fed daily until run off. She's Under a LED light. She is getting 350ppfd. She is About 2 or 3 weeks old. She was under a HPS bulb but the leaves started taco'ing so I switched her back over to a LED light and the leaves have got slightly better. She doesn't look happy. Nothing but problems with this grow.

 

[Delps8]

I think you've found the light saturation point for this plant.

Below are the light data for my most recent grow. It's typical of how I light my grows.




At "two or three weeks" the grow was getting 340 and 607µmol so your 350µmol isn't extreme for cannabis but it does look like it's a bit much for this plant but I suspect that there are other issues with the plant.

First step would be to drop the PPFD by 50 or 100µmol and observe the plant. My experience has been that when cannabis plants get too much light, the leaves return to their normal shape/position within 30 to 60 minutes. I say that because, almost invariably, I give my plants too much light in early veg so I turn the light down a bit, wait a day or two, and then bump the PPFD up again.

HPS gives of IR which tends to heat plants but I don't see anything heat-related. It does look like too many photons + something else. The something else is the larger leaves curling, one curling up, one curling down.

What are you using to measure light?

What about "wind"? Do you have a fan blowing across the plant/grow area?

RH is good. What about temp/VPD?

 

[Fish scale]

I think you've found the light saturation point for this plant.

Below are the light data for my most recent grow. It's typical of how I light my grows.


View attachment 5455077

At "two or three weeks" the grow was getting 340 and 607µmol so your 350µmol isn't extreme for cannabis but it does look like it's a bit much for this plant but I suspect that there are other issues with the plant.

First step would be to drop the PPFD by 50 or 100µmol and observe the plant. My experience has been that when cannabis plants get too much light, the leaves return to their normal shape/position within 30 to 60 minutes. I say that because, almost invariably, I give my plants too much light in early veg so I turn the light down a bit, wait a day or two, and then bump the PPFD up again.

HPS gives of IR which tends to heat plants but I don't see anything heat-related. It does look like too many photons + something else. The something else is the larger leaves curling, one curling up, one curling down.

What are you using to measure light?

What about "wind"? Do you have a fan blowing across the plant/grow area?

RH is good. What about temp/VPD?

I am using the photone app to measure how much ppfd they are getting. I have a fan that is facing the tent wall so they are only getting indirect airflow from the fan on the floor. The temps range from about 24c to 26c throughout the day. Humidity is around about 60% - 65%. I have raised my light a bit so they are only getting around 310ppfd - 320ppfd now

 

[Delps8]

I am using the photone app to measure how much ppfd they are getting. I have a fan that is facing the tent wall so they are only getting indirect airflow from the fan on the floor. The temps range from about 24c to 26c throughout the day. Humidity is around about 60% - 65%. I have raised my light a bit so they are only getting around 310ppfd - 320ppfd now

Photone- have you been able to calibrate it? Using a diffuser?

Check, check, check - all good stuff.

Dropping PPFD - certainly would not hurt. You're well into the "lotsa light" club now so dropping back and waiting a few days is a sound move.

The fact that the larger leaves are pointing down would indicate overwatering but that's not possible in coco, right (I grow in hydro)?

 

[Tvanmunhen]

I am using the photone app to measure how much ppfd they are getting. I have a fan that is facing the tent wall so they are only getting indirect airflow from the fan on the floor. The temps range from about 24c to 26c throughout the day. Humidity is around about 60% - 65%. I have raised my light a bit so they are only getting around 310ppfd - 320ppfd now

I would make sure your pH pen is calibrated just in case. Hopefully kicking the lights back helped.

 

[Wastei]

Probably low pH and too much ligh/high intensity. How do you measure runoff? If you take a reading from what's coming out in the beginning it will not be correct. Collect only the last few drops of the runoff to get a more true reading.

If you get the same runoff as you put in you're not doing it properly.

I typically run closer to pH 7.0 in veg growing in Coco coir since the minerals used in veg are more bio-avalaible at slightly higher pH above 6 going close to neutral. Coir get slightly acidic when being broken down.

Don't focus on light intensity in veg. They need very low intensity for proper growth rates. Especially at seedling stage whenever you see stress the first measure is to back off with the light.

Simple measures like total wattage and distance to the canopy is often better as a reference point since the app readings are all over the place depending on the phone and brand.

The photone app doesn't work for shit IMO. At least not on my phone without calibration.

Cheers!

 

[coreywebster]

I'd say bump your temps to 82f .

 

[Wastei]

I'd say bump your temps to 82f .

Good recommendation but I don't think that's the main problem.

I grow well with 24C/75F in Coco Coir, lower than that and you'll start seeing slower growth rates with certain strains.

Cheers!

 

[Fish scale]

Photone- have you been able to calibrate it? Using a diffuser?

Check, check, check - all good stuff.

Dropping PPFD - certainly would not hurt. You're well into the "lotsa light" club now so dropping back and waiting a few days is a sound move.

The fact that the larger leaves are pointing down would indicate overwatering but that's not possible in coco, right (I grow in hydro)?

I've changed from LED to HPS now because they just didn't seem like they were growing under the LED light. I haven't calibrated the photone app I just use it as it comes but since I've switched back to HPS I don't need to use the app anymore. And yeah you can't overwater in coco. I think I'm going to raise my feed from 0.7ml of A&B to 0.8ml of A&B because they have been getting 0.7ml now for about a week or two, maybe that will help solve the issues with her.

 

[Fish scale]

I would make sure your pH pen is calibrated just in case. Hopefully kicking the lights back helped.

Yeah it's definitely calibrated. I am using the Blue labs PH pen and I calibrated it about a week ago, I have switched from LED to HPS but they just don't seem like they are growing that much.

 

[Fish scale]

Probably low pH and too much ligh/high intensity. How do you measure runoff? If you take a reading from what's coming out in the beginning it will not be correct. Collect only the last few drops of the runoff to get a more true reading.

If you get the same runoff as you put in you're not doing it properly.

I typically run closer to pH 7.0 in veg growing in Coco coir since the minerals used in veg are more bio-avalaible at slightly higher pH above 6 going close to neutral. Coir get slightly acidic when being broken down.

Don't focus on light intensity in veg. They need very low intensity for proper growth rates. Especially at seedling stage whenever you see stress the first measure is to back off with the light.

Simple measures like total wattage and distance to the canopy is often better as a reference point since the app readings are all over the place depending on the phone and brand.

The photone app doesn't work for shit IMO. At least not on my phone without calibration.

Cheers!

My PH is 6.0 so I don't think it's that low? I was thinking about lowering it to 5.8 PH but I think PH 6.0 will do? I've got a 400w HPS on them at 28 inches away so I don't think it's that intense for them? I measure the run off in a saucer and just collect all of the run off from 1 plant and test it to see what it is. I could collect the last few drops of run off and test that to see what it's coming out at.

I thought the run off was supposed to be the same as it's going in?

they are about 3 or 4 weeks old now so I don't think they are seedlings anymore? They just ain't growing that much that's why they look small.

 

[Wastei]

My PH is 6.0 so I don't think it's that low? I was thinking about lowering it to 5.8 PH but I think PH 6.0 will do? I've got a 400w HPS on them at 28 inches away so I don't think it's that intense for them? I measure the run off in a saucer and just collect all of the run off from 1 plant and test it to see what it is. I could collect the last few drops of run off and test that to see what it's coming out at.

I thought the run off was supposed to be the same as it's going in?

they are about 3 or 4 weeks old now so I don't think they are seedlings anymore? They just ain't growing that much that's why they look small.

At transplant or a newly up potted plant you may see the runoff coming out lower than what you put in starting out. It takes a while for EC to stack and the medium to settle.

You typically aim to have the runoff 0.3 EC points above input in flower. I try to stay lower than 1.8 EC out on Sativa dominant and somewhere around 2.5 EC for plants with higher growth rates.

The reason I think pH is low is that's what typically happens after transplant in a coco coir before the medium settles.

Cheers!

 

[Fish scale]

I've noticed that she has got more and more yellow over time so by looking at the plant I am guessing she needs more feed since she went from looking green and healthy to yellow. I am going to increase my feed tomorrow and see how she responds to it.