lighting Leaves turned purple under Floro lights

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AlleninTampa

Hello
Been lurking for a few weeks now. I am sort of an experienced pepper grower, but have always done just regular varieties you can buy at the store (Jalapeño, cayenne, habanero, etc..)
This year I am doing some different varieties of super hots that I ordered.As my seedlings are popping up, the leaves (cotylendons) are turning purple within a few days. They are under a set of 2 Home depot 48" shop lights several inches above the seedlings. I realize the color is from the lights.My question is will it cause any long term damage to the plants? Is this a result of too much light? I usually germinate my seeds in my back screened porch with natural light, but this year it has been pretty cold, even for central Florida. So I have my "grow room" set up in my utility room where it stays warm

Thanks in advance
Allen
 
This happened to me last year. I replaced my cheapo flouro setup with an expensive bank of more powerful T5 lights, which promptly turned about 75 % of my seedlings purple. I thought I had killed them or something, but in the end it had no effect whatsoever on plant growth. Pulling up the lights a few inches will de-purple-fy the new leaves (the existing ones do not de-purple), but this seems to just be a cosmetic thing. Once the plants get outside in the sunlight, the new growth will be green and all will be well.
 
If you are using the standard 4' fluro setup that's several inches above your plants, it really sounds like a Phosphorus deficiency to me. I've had it with a few plants before. Give the affected plants a recommended dosage of ferts with micro-nutes.
 
No need to worry, its likely just anthocyanin pigment protecting your plants by giving them a purple suntan. Plants will be fine.
 
This is an interesting remark. I have my plants under a 250 w CFL, and all of my c. eximium are dark purple. Also one Bhut Jolokia has green leaves overshadowed with purple dots. I already contacted the person who send me the seeds, thinking that it may be a cross, but he has never grown any peppers with purple leaves, so he is puzzled.
I did find at a post at Gardenweb

"The most common cause of purple leaves (very common at this time of year) is a deficiency of phosphorus (P) because P is required to make ATP and ATP is needed to turn sugars to starch and to load sugar into phloem for transport. No P - no ATP - no move sugars/starches - anthocyanin (purple pigment) builds up - plant turns purple. The most frequent cause of a P deficiency is cold soils, which is why so many plants planted out too early turn purple.
A P deficiency is not the only suspect cause of purple leaves. Nearly any environmental condition that puts the brakes on growth and the accompanying use of sugars, but does not limit sugar production (photosynthesis) can cause anthocyanin buildup and purple leaves.

If only the outer edges of the leaves are purple, it may be a K or Mg deficiency. If the center of the leaves are also purple, it could be too much Ca in the soil or the result of too much water in the soil blocking uptake of P and Mg.

Do not apply a fertilizer with the middle number higher than either of the other two numbers (N & K) to container plants. There is never a need for that much P (relative to N) in container culture unless you're supplying only N in another form. Plants use about 6 times more N than P and the massive doses of P in 'bloom-booster fertilizers' cannot do any good."

I however doubt that a P deficiency is the cause, as the phenomenon is limited to the eximium, which have at the bottom 100% purple leaves, with more green at the top.
If the light is the cause, would you then not expect the top leaves to be purple instead?
 
Normal. Happens to mine all the time under my 125W CFL. I notice it mostly on Bhuts or other chinense.
 
AlleninTampa said:
Hello
Been lurking for a few weeks now. I am sort of an experienced pepper grower, but have always done just regular varieties you can buy at the store (Jalapeño, cayenne, habanero, etc..)
This year I am doing some different varieties of super hots that I ordered.As my seedlings are popping up, the leaves (cotylendons) are turning purple within a few days. They are under a set of 2 Home depot 48" shop lights several inches above the seedlings. I realize the color is from the lights.My question is will it cause any long term damage to the plants? Is this a result of too much light? I usually germinate my seeds in my back screened porch with natural light, but this year it has been pretty cold, even for central Florida. So I have my "grow room" set up in my utility room where it stays warm

Thanks in advance
Allen
Click to expand...
:welcome:

purple is ok....its just suntan for pepper plants
 
gvittman said:
Can we conclude from this that some varieties are more sensitive to the intense light than others?
Click to expand...
we can't compare the results are the setups are different with varying color temperatures,Ra, lumens ,etc.

unless someone come out with an experiment with one setup for all the different varieties of pepper plants.
 
Of all the pepper varieties I did this spring, the only one to have this issue was the BLACK JALAPEÑOS. Every single plant turned a deep purple until I was able to move them out to the porch with more natural light
 
Hmmm, I am not so sure about that. Personally have 3 containers with each 24 peppers, arranged according to size and under a 250 w CFL with Adjust-a-wing reflector. My annuum and rocopica are the tallest and as such the closest to the light source. They are nice and green. another container holds chinense (among which a few Bhut) and the eximium, and here all eximiums are dark purple at the bottom, green at the top. One bhut has purple spots on the leaves, all leaves. The 3rd container holds medium sized peppers, among which also a few bhut. Also here one bhut has the spotted leaves. The minimum distance between the CFL and the plants is about 15 inches, which may sound a lot, but the 250 W CFL does generate some nice heat.
You can easily say that for each container the color temp is the same (6400 K, is unchanged by distance and only determined by the spectrum of the light) and the light intensity is the same.
 
Sounds backwards to me. look at the evidence. the purple looks like it is caused by low light. get the light bulb closer to the plants.

I always get some purple also on tomatoes. Said to be cause by low temperature. It all goes away with high sun light outdoors when it warms up.

I allow all my plants to touch the cool fluorscent 40 watt 4 ft long light bulbs. The more light the better. light falls off as the square of the distance. stick them as close as possible to the lights. They will grow faster. It takes light to make photosynthesis. you are paying for the light so use it.
 
Tabby Basco said:
Sounds backwards to me. look at the evidence. the purple looks like it is caused by low light. get the light bulb closer to the plants.
Click to expand...

I only get purple on the plants under the 6 bulb T5 light, never on the ones under the T12 shop lights. The T5 puts out wayyyyyy more light than the T12s.

The leaves on all of my bhuts under the T5s are very purple, it definitely seems to me that they are more prone to the purple leaves than other varieties.
 
Thanks for mentioning the anthocyanin, for which Wiki gives an excellent description:
http://en.wikipedia.org/wiki/Anthocyanin

The anthocyanin could indeed be an explanation for the bhuts, but if so, then there is also a genetic factor playing. If not all the bhuts would show this phenomenon, and not just a few.
It however does not give an explanation for my eximium. Here is a picture which I took some weeks ago. Not very good because of the strong lighting, but is the best I could do.

IMG_1968.jpg


Notice the dark purple leaves at the bottom. A tan? OK. Will next time when on the beach get my shoes on when getting a too strong tan on my head. That should take care of it. :lol:
Sorry Potawie, am not at all making fun of you. It just came in my head.
 
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