My next experiment... 6500k vs 2700k for veg

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md.apothecary

Art is Resistance!
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My future plans are to test and experiment with 6500 and 2700 color spectrums for a full veg. phase. Yes, for the longest times people swear up and down about how the higher temps or spectrums are the way to go for veg phases. However! It is in my OWN personal experience that I see much better veg growth and development under nothing but 2700k at 18hrs than I do with 6500k at 18hrs.

I took some stunted plants out from under the 6500K CFLs and put them on the reverse side of the closet with 2700K CFLs, absolutely no difference in size bulbs or wattage, lumens, temps, etc. IDENTICAL conditions just different color spectrum. I even have the same brand bulbs purchased from the same walmart store on the SAME day, installed at the SAME time.

After 2 days in the 2700k, they started pushing out new branches. Started to smell, started to GROW! I am now a fond believer after another experiment in my grow box, that 6500K may not be that great after all. So, I am doing a veg grow with 6500k 105w CFLs in my new grow box now. If these don't do so great after a couple months, they're going to be flowered early and I will put in my 2700K 105w CFLs and start from seed all over again with the same strain as before and do a comparison grow, however, since this is a longitudinal experiment, it will take some time to complete, but I will try and post pictures up in my grow journal when seedlings sprout.

A link will be posted at that time. and this will be updated accordingly with experiment information...

if anyone else has some experience in this area, please let me know! Because I think that there IS a signficant difference. I can't believe the difference it made. The plants were stunted and not growing for a month and I got tired of it and transplanted them into bigger pots, and after another two weeks of nothing, decided to try the "light" idea that was boucning in my head the whole time. Sure enough!

Spooky!

After talking to another grower, he grows only under HPS lighting because of this very same reason. He'd get a great first couple weeks to a months worth of growing under a bluer spectrum light, then it just drops out to nothing. Under the HPS (which I saw his plants from start to finish under nothing but HPS) he had awesome results through the whole thing!

I want to almost venture and dare say that the blue spectrum might penetrate soil better than red spectrums, thus the initial boom in seedling growth to young/early veg phase, but that red might benefit more towards photosynthesis in upper portions of the plant causing the plant to grow better.

This might be the reason as to why so many people add red spectrum lighting as supplimental lighting to their flouroscent grows... hmmmmmmmmm........ IDK... IJDK
 
Looking forward to your experiment, good luck. I have read that some just use HPS only and have great results.
 
You know I'm always interested in what your experiments lead to. Been thinking of a cfl grow, your results would make a lot of sense and benefit many people here.
 
good luck man ill be watching this one cause i plan on investing in some new light for veg some time in the future so this expermient will bee good for me to keep a eye on good luck










HAPPY GROWIN TOM TOM
AND HAPPY SMOKIN
 
It will be interesting to see the results for sure, couple of questions though...

what do you intend on doing to record the results will you be measuring height or couting nodes and final leaf development if it comes down to it

how many will you be testing on, will it be just 1vs1 or will it be more?
 
Currently, I have 4 plants germinated from seed. I planted them in soil last night and will be counting from this point on the following:

I will be measuring from a standard height position from the tops of the pots to the lights which is set at: 10"

I will be counting days to germinate (breaking of soil and releasing of seed pod). And of course the percentage of actual seeds germinated. However, this will create some uncertainty due to seed health, but will be taken into consideration anyway.

I will count rate of growth daily.

I will count length of stretch and number of nodes.

I will also try and measure as accurately as possible the leaflet size and leaf count.

Overall height will also be measured in an allotted time period. Results will end either at 1 month or longer depending on plants.
 
Well there are some big differences is color ratings with HID lights and CFLs - a 2700k rating for a HPS really is strongly in the red-orange-yellow and drops off hard into the blues, where a CFL rated 2700k has only a modest boost in warms, and is really a full spectrum light with a strong amount of blue despite it being rated 2700k.
I've vegged with the 2700k CFLs and you couldn't ask for denser plants, but I think mixing in a 6500 would have been ever better. But the bulb switching with CFL is much less of a change as it is going from MH to HPS, and even with those, people do whole grows with either one and are highly successful. MH I have read many times will produce a higher quality bud, but HPS gets the higher lumen/watt ratio and is used more often for that reason more than for its spectrum qualities.
 
There is a lot of difference between 6500k and 2700k in CFLs, and this is obvious by the color of the light visually, and through the photo imaging and spectral graphs. There is no doubt about it.

AlienBaits graph showing plant requirements. This is HPS light output. The line indicates plant sensitivity curve.
EYE_HPS_conversion_graph.jpg


6500k CFL SPECTRAL GRAPH (provided by GE)

image004.jpg


2700K CFL (BY GE)
warm_white.jpg


There is still some blue as you mentioned, but not THAT strong of a blue spectrum where as the red is definitely spiked.
 
Well good luck md. This'll be an interesting experiment.

I always like to see side by side comparisons.
 
what about flowering with hps and floros? more variety in the color spectrum. This would be a interesting experiment
 
I gave up my HPS due to heat issues that were uncontrolable, but CFLs were the next way to go. People said CFL's put off more heat to get the same amount of light. However, this might be true, but most people buy a 400w HPS to start with and they may not require that much light as far as lumens is concerned, and to cut costs and corners concerning heat you could reduce your HPS size, but for me just wasnt practical.

This experiment is mostly focusing on 6500K cfl vs. 2700k cfl because everyone knows that theoretically, HPS should put off more bud than CFL when in flower mode. but I have seen some remarkable CFL grows using envirolites and over 4oz of bud in a small grow cabinet and only 3 plants. That was an incredible yield.

I might tackle that issue later, but right now this has me wondering, because if it proves true and someone else can replicate it, you might be able to cut out the whole veg light theory all together.
 
Well, ironically enough, the pups havent done squat! This is exactly what I figured would happen. They grow a couple inches and cease. Either it is the specific color spectrum of 6500k or some other means.

SO, all in all, here's what I am going to do! I will be letting these hang out in the 6500k light until the end of this month and until the fat daddy 2700k bulbs arrive and I will give those a shot and see what happens in comparison.

It's so bad I couldn't even DO a journal... nothings growing!
 
I just saw a grow on another grow site this guy is using a 200w hps from start to finish. The plant is like 6 inches wide and about as tall as a AA battery.
http://www.marijuanagrowing.eu/cannabis29582-0-asc-10.html
But that is in the seedling stage. However I have seen one grow I really liked, the guy had one cab for veg and flower with 6 42w 2700k cfl and would just use that from start to finish on 12/12 and growing in 20 oz coke bottles, man were his plants nice, and such a simple setup. Great for a personal grow. Thats like 15-20 a month for electric. I know what you're thinking MD. All the grows I've read that use the 2700k from start to finish had great plants. I'll be watchin.
 
I must agree that so far, CFL growing has been my favorite, however, CFLs in 6500k just don't seem to do it! I have yet to change over to give them a little more timing in the case as I am seeing some very very slow growth in the seedlings. I want to switch over relatively soon though. Maybe after valentines day. I have to start looking for some other high cost items at the moment before I can fully complete the switch of bulbs (I've yet to order them) :cool:
 
I love experiments. I've tried it myself, using just the 6500k, just the 2700k and using a mixture of both during all phases of growth. I found that, in veg, a mixture of the two lamps did the best, followed by 6500k, and 2700k. In flower, I found the exact opposite to be true; 2700k did best, followed by 6500k and strangely, the mixture of the bulbs during flower showed quite a noticeable decrease in growth. I can't wait to see your results to see how we compare.
 

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