Heat stress? Light stress? Help!

[GenieMan]

Not sure if its heat stress or light stress? I usally keep my grow light about 24 inches. I have a King Plus 600 watt ( 125 watt real power) LED. My temps are usally in the mid 70's and my humdity is mostly between mid 50's. I have my plant in the open down in my basement. I did have a fan blowing ovee the top but turned if off for now until I can figure this out. I PH'd my soil while wet with a soil meter which gave me a mid 7 but I also PH'd my soil while dry using a soil test kit which came in at 6.5. I'm using Fox Farm Ocean Forest with no additives. I recently just started using Dr Earth Bud - Bloom nutes half strength. I also got a 120x microscope and didn't see any critters on the top of the leaf. I live in CT so I don't think it would be russet mites. I'm also about 5 weeks into this grow and it's a Northern Light Auto. Oh ya, I water with distilled water every 5 or so days. I let the soil get pretty dry and wait for some run off to come out the bottom. Thanks for any advice.

 

[GenieMan]

Also run the lights 20/4

 

[Mugwort]

Not sure if its heat stress or light stress? I usally keep my grow light about 24 inches. I have a King Plus 600 watt ( 125 watt real power) LED. My temps are usally in the mid 70's and my humdity is mostly between mid 50's. I have my plant in the open down in my basement. I did have a fan blowing ovee the top but turned if off for now until I can figure this out. I PH'd my soil while wet with a soil meter which gave me a mid 7 but I also PH'd my soil while dry using a soil test kit which came in at 6.5. I'm using Fox Farm Ocean Forest with no additives. I recently just started using Dr Earth Bud - Bloom nutes half strength. I also got a 120x microscope and didn't see any critters on the top of the leaf. I live in CT so I don't think it would be russet mites. I'm also about 5 weeks into this grow and it's a Northern Light Auto. Oh ya, I water with distilled water every 5 or so days. I let the soil get pretty dry and wait for some run off to come out the bottom. Thanks for any advice.

 

[Mugwort]

Judging by internodal distance I’d say move the light closer. Turning up of leaves can mean overwatering but the folds on your leaves are sharp and close to the edge so I’m not sure but I don’t see excess light being the problem.

 

[GenieMan]

Ya its weird. Idk. I think its a VPD problem but than again why only the leafs closer to the top? Id think the whole plant would be like that? Ill move the light closer and keep an eye out. Thanks.

 

[dbrzz]

Not sure if its heat stress or light stress? I usally keep my grow light about 24 inches. I have a King Plus 600 watt ( 125 watt real power) LED. My temps are usally in the mid 70's and my humdity is mostly between mid 50's. I have my plant in the open down in my basement. I did have a fan blowing ovee the top but turned if off for now until I can figure this out. I PH'd my soil while wet with a soil meter which gave me a mid 7 but I also PH'd my soil while dry using a soil test kit which came in at 6.5. I'm using Fox Farm Ocean Forest with no additives. I recently just started using Dr Earth Bud - Bloom nutes half strength. I also got a 120x microscope and didn't see any critters on the top of the leaf. I live in CT so I don't think it would be russet mites. I'm also about 5 weeks into this grow and it's a Northern Light Auto. Oh ya, I water with distilled water every 5 or so days. I let the soil get pretty dry and wait for some run off to come out the bottom. Thanks for any advice.

Leaves curling up is from lack of water stress. The leaves are preserving their moisture levels by curling up. Healthy hydrated leaves are flat. High salt levels in the grow medium can reduces water uptake also.

 

[ComfortablyNumb]

Chronic Underwatering.

Basic Watering

Marijuana Watering, how media, pot size/shape and environment affect it

Discuss different watering methods for growing your own weed from seeds. Our community members give helpful tips on how pot size and material, as well as environmental factors affect growing cannabis.

www.thcfarmer.com

Watering SOIL

New Simplified Way to Water Marijuana Plants

To know if you need to water your cannabis plant get yourself a soil meter. Poke or drill 4 holes in your pot 1/4 way up from the bottom spaced around the pot...

www.thcfarmer.com

Watering COCO

HOW TO WATER COCO FOR BEST RESULTS.

Ok writing this cause i see this issue often and rather have a thread to link than explain this each time. This is not my work but a collection of info from many members here and I have put into practice myself. So first off COCO is NOT soil. For best results we want to keep it saturated...

www.thcfarmer.com

 

[TSD]

It looks pretty dry... gotta remember to up the water as they grow bigger... also it's pretty stretched... so I would say the light could go a little closer.

 

[dbrzz]

Not sure if its heat stress or light stress? I usally keep my grow light about 24 inches. I have a King Plus 600 watt ( 125 watt real power) LED. My temps are usally in the mid 70's and my humdity is mostly between mid 50's. I have my plant in the open down in my basement. I did have a fan blowing ovee the top but turned if off for now until I can figure this out. I PH'd my soil while wet with a soil meter which gave me a mid 7 but I also PH'd my soil while dry using a soil test kit which came in at 6.5. I'm using Fox Farm Ocean Forest with no additives. I recently just started using Dr Earth Bud - Bloom nutes half strength. I also got a 120x microscope and didn't see any critters on the top of the leaf. I live in CT so I don't think it would be russet mites. I'm also about 5 weeks into this grow and it's a Northern Light Auto. Oh ya, I water with distilled water every 5 or so days. I let the soil get pretty dry and wait for some run off to come out the bottom. Thanks for any advice.

Your light isnt strong enough to stress the plants. The internodal distance on your stems indicate low light levels and stretching is the result. I have a bud at 6 inches from the SF4000 and the main bud is bigger than the rest, which are around 16-24 inches from the light. Heat from the light itself is usually the stressor. Unless you are pushing high par value lights, which would be several thousand dollars for high output lighting, you cant give excessive light with budget grow lights. Budget meaning $1000.00 or less for a 4x4 space.

 

[Mugwort]

Your light isnt strong enough to stress the plants. The internodal distance on your stems indicate low light levels and stretching is the result. I have a bud at 6 inches from the SF4000 and the main bud is bigger than the rest, which are around 16-24 inches from the light. Heat from the light itself is usually the stressor. Unless you are pushing high par value lights, which would be several thousand dollars for high output lighting, you cant give excessive light with budget grow lights. Budget meaning $1000.00 or less for a 4x4 space.

Hey dbrzz...your comment regarding par value and lights implying spending “$1000 or less” meeting the lighting needs for a “4x4 space” caught my eye!
Are you saying that all I am doing when I added a second ViparSpectra XS 2000 led light to my 4x4 was create a potential heat problem from excessive radiation from other bandwidths of light outside of the 400 - 700nm range of photosynthetic active light the cannabis plant uses?

Your sf4000 is a great light but I am confused...The sf4000’s specs indicate it is adequate for 4x4 flower coverage and is well under $1000. In my rush to get a light I was growing my first plant (ever) in a closet. I later purchased a 4x4 tent and realized my xs2000 may not deliver adequate coverage when I started to use a SCROG net and wanted to utilize every sq ft of area in tent. I felt I should have purchased the XS4000 or the SF4000 so I added another XS2000, raised both lamps higher above canopy, and turned down the intensity of both lamps to 75%. Are you saying that this is the major difference between a 700-$800 led light like yours—PAR signatures? An expensive (>$1000) led has LESS radiation of unuseful, non-par spectrum light, i.e. the ratio of non-par to par light is less as you pay more?

 

[dbrzz]

Hey dbrzz...your comment regarding par value and lights implying spending “$1000 or less” meeting the lighting needs for a “4x4 space” caught my eye!
Are you saying that all I am doing when I added a second ViparSpectra XS 2000 led light to my 4x4 was create a potential heat problem from excessive radiation from other bandwidths of light outside of the 400 - 700nm range of photosynthetic active light the cannabis plant uses?

Your sf4000 is a great light but I am confused...The sf4000’s specs indicate it is adequate for 4x4 flower coverage and is well under $1000. In my rush to get a light I was growing my first plant (ever) in a closet. I later purchased a 4x4 tent and realized my xs2000 may not deliver adequate coverage when I started to use a SCROG net and wanted to utilize every sq ft of area in tent. I felt I should have purchased the XS4000 or the SF4000 so I added another XS2000, raised both lamps higher above canopy, and turned down the intensity of both lamps to 75%. Are you saying that this is the major difference between a 700-$800 led light like yours—PAR signatures? An expensive (>$1000) led has LESS radiation of unuseful, non-par spectrum light, i.e. the ratio of non-par to par light is less as you pay more?

Whaaaat?????? “$800 led light like yours—Par signatures?”
1. I didnt discuss my light sets.
Simply, I dont think you have spent enough $$$$ on lighting to worry about too much Photon energy output.

 

[ComfortablyNumb]

Your light isnt strong enough to stress the plants. The internodal distance on your stems indicate low light levels and stretching is the result. I have a bud at 6 inches from the SF4000 and the main bud is bigger than the rest, which are around 16-24 inches from the light. Heat from the light itself is usually the stressor. Unless you are pushing high par value lights, which would be several thousand dollars for high output lighting, you cant give excessive light with budget grow lights. Budget meaning $1000.00 or less for a 4x4 space.

I have $300 of light in our 4x4. My meter reads the sun at 940 on a clear day at noon. My el-cheapos read 1875 at 20 inches at 50%

 

[dbrzz]

Nice

 

[ComfortablyNumb]

Good lights are out there. You just have to do a little digging.

 

[Madmax]

I reckon your close..heat or light.i have slight tacoeing on my tops near like yours but if you look at the rest (lower) they are fine.if it was lacking water the whole plant tops will droop from the petitoles .id just move light up a little..

 

[Mrb53]

Back to the issue at hand
I see stuff like that from windburn too. Just something to look at. I do not see the leaf curl at the bottom, only the top so that is why most are saying light burn. Heat will affect the whole plant, light affects the closest spots first, wind - where ever it is hitting so deflecting it helps or instead of positive (blowing on), switch it to negative (sucking air away like a fan on a heatsink in a pc does, it pulls the heat / air out

 

[growsince79]

Your light isnt strong enough to stress the plants. The internodal distance on your stems indicate low light levels and stretching is the result. I have a bud at 6 inches from the SF4000 and the main bud is bigger than the rest, which are around 16-24 inches from the light. Heat from the light itself is usually the stressor. Unless you are pushing high par value lights, which would be several thousand dollars for high output lighting, you cant give excessive light with budget grow lights. Budget meaning $1000.00 or less for a 4x4 space.

soo wrong. A $5 light can hurt a plant if its too close.

 

[dbrzz]

Hey dbrzz...your comment regarding par value and lights implying spending “$1000 or less” meeting the lighting needs for a “4x4 space” caught my eye!
Are you saying that all I am doing when I added a second ViparSpectra XS 2000 led light to my 4x4 was create a potential heat problem from excessive radiation from other bandwidths of light outside of the 400 - 700nm range of photosynthetic active light the cannabis plant uses?

Your sf4000 is a great light but I am confused...The sf4000’s specs indicate it is adequate for 4x4 flower coverage and is well under $1000. In my rush to get a light I was growing my first plant (ever) in a closet. I later purchased a 4x4 tent and realized my xs2000 may not deliver adequate coverage when I started to use a SCROG net and wanted to utilize every sq ft of area in tent. I felt I should have purchased the XS4000 or the SF4000 so I added another XS2000, raised both lamps higher above canopy, and turned down the intensity of both lamps to 75%. Are you saying that this is the major difference between a 700-$800 led light like yours—PAR signatures? An expensive (>$1000) led has LESS radiation of unuseful, non-par spectrum light, i.e. the ratio of non-par to par light is less as you pay more?

No. Your lighting is great. I am saying before you experience par value higher than your plants can take without light stress, heat from the lights will be more of a problem than excessive light values.

 

[brotherfrombelgium]

IMO i would say it could possibly be a combination of toxic salt build up, heat stress or even a lack of water.

When leaves try and dissipate water and can't it 's mostly because of those top 3.

 

[Mrb53]

toxic salt buildup is evident when the Ph out is greater than the ph in...the salts change the ph
lack of water - plant droops, soil is light OR you have no Oxygen in the substrate - - aerate, oxygenate the water / feedings
heat stress - if it is that bad, leaves may canoe or the whole plant stresses. My summer garden grow went through that...hard to deal with