Showing signs of too much light with 250W HPS

edcocks

Well-Known Member
Cabinet grow with Lowryder 2 in soil (foxfarm ocean in 2 gallon pots)and my plant is 5 weeks old and budding nicely. It is short (5inches) and showing signs off too much light. The cabinet is dresser sized using 250watts HPS shining about 4 inches above the girl. She Is getting bleached and developing light colored leaves aside from the normal color green ones that are shielded from the light. Ventilation is overkill and keeps the temps in the 70's F. The plant is only 5 inches tall and budding nicely - it's A dwarf strain, but it's still shorter than it Should be. Lights are on 24/0 because they are the heat source as this cabinet is in the attic and it's winter. My research on this forum tells me that I should raise the lights to cut down the intensity a bit.

I would post pics, but have not been able to figure out how to with an Iphone.
 

indyman

Active Member
Cabinet grow with Lowryder 2 in soil (foxfarm ocean in 2 gallon pots)and my plant is 5 weeks old and budding nicely. It is short (5inches) and showing signs off too much light. The cabinet is dresser sized using 250watts HPS shining about 4 inches above the girl. She Is getting bleached and developing light colored leaves aside from the normal color green ones that are shielded from the light. Ventilation is overkill and keeps the temps in the 70's F. The plant is only 5 inches tall and budding nicely - it's A dwarf strain, but it's still shorter than it Should be. Lights are on 24/0 because they are the heat source as this cabinet is in the attic and it's winter. My research on this forum tells me that I should raise the lights to cut down the intensity a bit.

I would post pics, but have not been able to figure out how to with an Iphone.
my 400 watt is 6in from top of my canopy and do not have that prob trans plant in to 3+ gal pot and see what happens and give big bloom from fox farms the shit works great and in flower i use tiger bloom as well,good luck
 

jawbrodt

Well-Known Member
^My 400 watt bleaches leaves at 10-12", because that's the difference of have a vented of unvented hood. You lose a good percentage of intensity through that glass, more than you would think. At 4", there's no doubt in my mind that the 250 watter is bleaching his plants. It's probably reading over 10,000 lumens at that distance, i'd bet on it. Anyway...yeah, you should raise that light to about 10-12", and you'll still be getting output in the 4000 range, which will work excellent. :)
 

resinraider

Well-Known Member
Hving ur light too close will do this? What r early signs? I have my 1000 like 6-8"s off my canopy but its on a rail. Do u think that's too close? I don't see any probs with my leaves and its been like this for like 2-3 weeks
 

jawbrodt

Well-Known Member
Hving ur light too close will do this? What r early signs? I have my 1000 like 6-8"s off my canopy but its on a rail. Do u think that's too close? I don't see any probs with my leaves and its been like this for like 2-3 weeks

You're safe because you're using a rail. If you were to keep it in one spot, you'd be having problems. That's one of the advantages of using rails, and i plan to try one out pretty soon. :)
 

BlueFish

Active Member
The intense light causes a ton of heat in the air which can damage the plants through convection, plus the direct heat through radiation. Convection isn't a problem unless your air is stagnant and the temps in your grow room get really high. Radiation is a problem whenever the heat being radiated builds up long enough. Having a rail makes sure it's not too intense on any one spot for very long and little heat builds up. If the light is stationary, however, it keeps heating the same spot and you get heat damage. The intense light also has a powerful bleaching effect unrelated to the heat.
 

jawbrodt

Well-Known Member
I've been getting bleaching in my bloom room, in the spots where i'm getting 7000+ lumens. This might sound strange, but i swear the intense light, and the stress from it, makes for more potent bud. If i wait til the end of bloom, them hammer them with intense light for the last 2 weeks, they are stronger. I don't have enough light to do that to the whole bloom room, so that allows me sample stuff from areas of different intensity, and compare. Interesting experiment, but i haven't been doing it long enough to have any concrete results, so I'll post my results when I find out for sure. :)
 

brasmith

Well-Known Member
Cabinet grow with Lowryder 2 in soil (foxfarm ocean in 2 gallon pots)and my plant is 5 weeks old and budding nicely. It is short (5inches) and showing signs off too much light. The cabinet is dresser sized using 250watts HPS shining about 4 inches above the girl. She Is getting bleached and developing light colored leaves aside from the normal color green ones that are shielded from the light. Ventilation is overkill and keeps the temps in the 70's F. The plant is only 5 inches tall and budding nicely - it's A dwarf strain, but it's still shorter than it Should be. Lights are on 24/0 because they are the heat source as this cabinet is in the attic and it's winter. My research on this forum tells me that I should raise the lights to cut down the intensity a bit.

I would post pics, but have not been able to figure out how to with an Iphone.
Well then everyone is just guessing on what your plant issue is. Not only are they guessing, the answers agree with your diagnosis. Your plants probably have a problem that is not related to light, but then again I'd be guessing without pics.
 

cowell

Well-Known Member
here is a chart that may help
was going to put the same chart up and say ... i have a 250 HPS over my plants vegging before flower and I found that about 8" away is perfect as if they grow a bit.. I don't have to always check the height or worry about it getting too close. You'll figure out what works for you, but that chart has come in handy for me too as I was setting things up.
 

cowell

Well-Known Member
Well then everyone is just guessing on what your plant issue is. Not only are they guessing, the answers agree with your diagnosis. Your plants probably have a problem that is not related to light, but then again I'd be guessing without pics.
Good point.. rep+.. but..

The light issue isn't a guess. I know, and I'm not disputing or dis-agreeing with you that if there were pics it could be a combination of things like nutes etc.. and not a light issue at present.. maybe his light is far enough away .. but he said 4".. that's too close. I don't need pics to be accurate in diagnosing that if his info is correct.l

OP- he's right thought you should post pics for the complete diagnosis.
 

edcocks

Well-Known Member
Well then everyone is just guessing on what your plant issue is. Not only are they guessing, the answers agree with your diagnosis. Your plants probably have a problem that is not related to light, but then again I'd be guessing without pics.
Okay here goes a try at pics as your point is valid. I'm not a camera guy so bear with me. The other plants in the back are normal green and about 3 weeks behind the bigger one. It's a whopping 5 inches tall. I raised the lights yesterday and it does seem to already be helping with a darker green color developing longitudinally down the center of the newer leaves. the yellowing seen on the lower leaves on the pic are not real due to light distortion from my poor camera skills.
 

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brasmith

Well-Known Member
Okay here goes a try at pics as your point is valid. I'm not a camera guy so bear with me. The other plants in the back are normal green and about 3 weeks behind the bigger one. It's a whopping 5 inches tall. I raised the lights yesterday and it does seem to already be helping with a darker green color developing longitudinally down the center of the newer leaves. the yellowing seen on the lower leaves on the pic are not real due to light distortion from my poor camera skills.
Your camera skills are good it is just the hps that is making your pics look orangish. You could turn off the hps and use the flash from your camera and then turn the light back on. From what I can see however the plants look good the leaves have nice shape and development. The one that is flowering is lovely.

4 inches is pretty close for 250 watts so moving it was perfect even if the issue is not related to lights.

Do you have any spots or discoloration on your leaves? How about your ph? What about that darker green color of your leaves you mentioned?
 

brasmith

Well-Known Member
Good point.. rep+.. but..

The light issue isn't a guess. I know, and I'm not disputing or dis-agreeing with you that if there were pics it could be a combination of things like nutes etc.. and not a light issue at present.. maybe his light is far enough away .. but he said 4".. that's too close. I don't need pics to be accurate in diagnosing that if his info is correct.l

OP- he's right thought you should post pics for the complete diagnosis.
Hi Simon.....ahhheemm.....cowell. Thanks for the +rep. Your point is extremely valid and to tell you the truth I missed that tiny "4 inches away" detail, haha. Which is why I came off harsh. +rep for you for being dead on with info and making sure I stayed in line.:clap::weed:
 

edcocks

Well-Known Member
The flowering plant is getting better and a darker green after moving the light to about 12 inches two days ago. That was the problem. It's just odd to me that that was the problem. I have read on many threads that you put the lights as close as possible without burning the plants. Guess that's horse shit. Doing just that has probably affected my last few grows. My cabinet is totally tuned minus the CO2 so I knew there was a simple explantion to my lower than average lowryder 2 yields.
 
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