led lights,problems growing with led, plant problems & diagnostics, sick plants, lets have a discussion ??

Jaydee86 · Jan 4, 2022

Hi guys whats growing on?? so......ive been having some issues lately growing with led lights, well im assuming its because of led lights anyways im on my 4th time round consistently killing my girls and this shit is really getting to me!, so ive been through the whole interweb twice and the only logical theory that i can come up with is that when growing with led lights the transpiration rates are different or behave differently am i right??
so what was happening is im seeing people getting symptoms of overwatering their plants, when infact 90% of the time these people including myself are having these issues and just completely mind blown, scratching my head wondering wtf is going on?? how can i be overwatering my plants ive never had this problem before!, anyways ive put my girls back under conventional lighting (hps) and then things start to look better! im totally stunned like i just cant believe these led lights could be my problem, or atleast in theory??
so my understanding is that water/nutrients get sucked up through the roots, up through the plant and exits via the leaves (transpiration), but under led lights the leaf temperatures are quite a bit lower due to the lack of infrared heat i believe which greatly reduced transpiration rates? so if this water/nutrients have nowhere to go then its all like blocked up with nowhere to go and starts to drown the plant? causing symptoms of what we normally would think to be overwatering?
guys im still trying to figure all this out but i think im on to something here and i think this might be the problem ive been dealing with for so long.
ill post some pics up when i get on my phone later and hopefully some of you smart guys read this and help figure this shit out.
thanks to anyone that takes the time to read this and can offer some advice much appreciated.

Jaydee86 · Jan 4, 2022

2Bad · Jan 4, 2022

Aye! I read the whole post but to me it looks like your LED's are just too close/strong. My Marshydro needs to sit at 36 inches or I have issues.

mysticepipedon · Jan 4, 2022

So are your temperatures lower in the grow room? That can definitely have an effect.

The learning curve that I had was with burning when I didn't have sufficient Mg.

Jaydee86 · Jan 4, 2022

2Bad said:
Aye! I read the whole post but to me it looks like your LED's are just too close/strong. My Marshydro needs to sit at 36 inches or I have issues.

What mars hydro light do you have? Do you keep it at one setting or gradually increase it? I didn't find any difference in increasing the distance of the lights.

Jaydee86 · Jan 4, 2022

mysticepipedon said:
So are your temperatures lower in the grow room? That can definitely have an effect.

The learning curve that I had was with burning when I didn't have sufficient Mg.

Thanks for the reply, so yea it's winter now and with led lights both running I'll get max reading of about 24°c and that's from my probe hanging at about plant canopy level.
I'm thinking maybe leaf surface temperature(lst) will be a bit lower?
I've never had these issues before and I have friends that grow using the same system but with hps and they have never had this problem.
It's fucking messed up, makes your brain go crazy trying to solve something that you don't quite understand.

Chem77 · Jan 4, 2022

Jaydee86 said:
Thanks for the reply, so yea it's winter now and with led lights both running I'll get max reading of about 24°c and that's from my probe hanging at about plant canopy level.
I'm thinking maybe leaf surface temperature(lst) will be a bit lower?
I've never had these issues before and I have friends that grow using the same system but with hps and they have never had this problem.
It's fucking messed up, makes your brain go crazy trying to solve something that you don't quite understand.

24 Celsius is not warm enough, I had to add heat. Not a problem since.
Hps’s blast a lot of heat.

Jaydee86 · Jan 4, 2022

I actually ran hps+led combo and still was getting problems.
It's a proper headfuck! It's either got to be the leaf surface temperature or the intensity of the led light.
I did get 1 good run with the led lights but that was through the summer while temps were quite high so I wonder if that's why it was ok then?

Jaydee86 · Jan 4, 2022

Chem77 said:
24 Celsius is not warm enough, I had to add heat. Not a problem since.
Hps’s blast a lot of heat.

How did you add heat in the end? Did you use a heater or something?

AlfaDog · Jan 4, 2022

The ambient room temp is a good reference but there's so many factors sized of the room etc... your canopy should be around 83-85 and with co2 could go up to 87° you never mention what the canopy temp is start with that since leds don't have much to none infrared like hps so you have to run hotter for the stomata They open to absorb CO2. They close to retain moisture.....and all fans do in a room is to create air movement so air isn't stagnant but it looks like you might be hitting your plants hard reson I say this is because if your plants are trying to sweat but your hitting them with all kinds of wind they can't properly sweatand prob bringing canopy temps low. The plants are very stressed and I assumeits a combination and make sure your introducing new air and throwing out that old hope there not drowning in there own co2 So start with getting leaf canopy temp up to 83-85 see how they react. Then make sure that fan isn't hitting them and your exhausting that air outside and give new

2Bad · Jan 4, 2022

Jaydee86 said:
What mars hydro light do you have? Do you keep it at one setting or gradually increase it? I didn't find any difference in increasing the distance of the lights.

fce 4800 but i started with a couple fluorescents ...you have to gradually increase especially when starting with fluors

Jaydee86 · Jan 4, 2022

So I don't have a laser thermometer to check leaf temps but they're under hps now and look like they're doing better.
But what you're saying makes sense man with the stomata opening up at higher temps, and I think with my leaf temps being low under led, the plants act like they're being overwatered.
I don't have an oscillating fan going but I do have fresh air coming in down low and exhaust air up top going outside so its quite a nice atmosphere with the air being exchanged and obviously running negative pressure so the air goes out a little bit faster than it comes in.

mysticepipedon · Jan 4, 2022

Jaydee86 said:
Thanks for the reply, so yea it's winter now and with led lights both running I'll get max reading of about 24°c and that's from my probe hanging at about plant canopy level.
I'm thinking maybe leaf surface temperature(lst) will be a bit lower?
I've never had these issues before and I have friends that grow using the same system but with hps and they have never had this problem.
It's fucking messed up, makes your brain go crazy trying to solve something that you don't quite understand.

Cold weather is only starting to set in where I live, so my next grow will probably be under HIDs. Last winter was colder and I needed to add a space heater outside the tents, destroying any energy savings from the LEDs.

Jaydee86 · Jan 4, 2022

So I don't have a laser thermometer to check leaf temps but they're under hps now and look like they're doing better.
But what you're saying makes sense man with the stomata opening up at higher temps, and I think with my leaf temps being low under led, the plants act like they're being overwatered.
I don't have an oscillating fan going but I do have fresh air coming in down low and exhaust air up top going outside so its quite a nice atmosphere with the air being exchanged and obviously running negative pressure so the air goes out a little bit faster than it comes in.

mysticepipedon said:
Cold weather is only starting to set in where I live, so my next grow will probably be under HIDs. Last winter was colder and I needed to add a space heater outside the tents, destroying any energy savings from the LEDs.

Would almost make sense to go with hid lights and maybe add an led as suppliment lighting? Either way let us know how you get on

AlfaDog · Jan 4, 2022

Jaydee86 said:
So I don't have a laser thermometer to check leaf temps but they're under hps now and look like they're doing better.
But what you're saying makes sense man with the stomata opening up at higher temps, and I think with my leaf temps being low under led, the plants act like they're being overwatered.
I don't have an oscillating fan going but I do have fresh air coming in down low and exhaust air up top going outside so its quite a nice atmosphere with the air being exchanged and obviously running negative pressure so the air goes out a little bit faster than it comes

So the only thing I can figure out and you mentioned you haven't cheaked in the past your canopy temps so your plants are too close and temps at canopy are too high and they are cupping so the stomata can't release moister and exchange co2 and oxygen that's where the cupping/drooping. I usto run only hps and took a pause growing I came back 5 years later and it's all about LEDS I understand brother don't give up its just a Learning curve and that's what makes growing so awsome never stop learning

Chem77 · Jan 4, 2022

Chem77 said:
24 Celsius is not warm enough, I had to add heat. Not a problem since.
Hps’s blast a lot of heat.

Last year I added a tower heater being my first winter with LED’s. This year I replaced my mini split a/c with a/c and heat mini split. I also added a tiled heated floor that is on a digital thermostat.

Chem77 · Jan 4, 2022

Jaydee86 said:
How did you add heat in the end? Did you use a heater or something?

Post above, hit reply on wrong post.

Jakecan · Jan 4, 2022

Forsure invest in an infrared thermometer and check the leaf temp. Try to get your VPD to optimal range and maybe an oscillating fan rather than stand still. You're right tho it does look like over watering.

RollingBall · Jan 4, 2022

Jaydee86 said:
So I don't have a laser thermometer to check leaf temps but they're under hps now and look like they're doing better.
But what you're saying makes sense man with the stomata opening up at higher temps, and I think with my leaf temps being low under led, the plants act like they're being overwatered.
I don't have an oscillating fan going but I do have fresh air coming in down low and exhaust air up top going outside so its quite a nice atmosphere with the air being exchanged and obviously running negative pressure so the air goes out a little bit faster than it comes in.

Would almost make sense to go with hid lights and maybe add an led as suppliment lighting? Either way let us know how you get on

I like this for night time temp control. Amazon

350W Space heater, Wall Outlet Electric Space Heater

Moshmen · Jan 4, 2022

All great advice but I lean towards vpd as A good starting point.

led lights,problems growing with led, plant problems & diagnostics, sick plants, lets have a discussion ??

led lights,problems growing with led, plant problems & diagnostics, sick plants, lets have a discussion ??

Jaydee86

Jaydee86

2Bad

mysticepipedon

Jaydee86

Jaydee86

Chem77

Jaydee86

Jaydee86

AlfaDog

2Bad

Jaydee86

mysticepipedon

Jaydee86

AlfaDog

Chem77

Chem77

Jakecan

RollingBall

350W Space heater, Wall Outlet Electric Space Heater​

Moshmen

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