is 6500k the optimum kelvin temp for vegging?? or would a higher temp, say 10,000k or 15000k be better?
my question isnt really dependent on what type of light. i would be using cfl or t5's...so is it better to use 6500k or a higher kelvin temp like 15000k for veg? anyone?
i would say it has prob been tested that 6500 was best but i think it falls into normal sun given ranges- perhaps thats as high as it gets naturally so maybe higher would kill it or make it better--u should try it- <stoned
OK I just found a light with a color temp of 9325k: http://1000bulbs.com/product.php?product=32672 If I were you I would not try to reinvent the wheel and just stick with the 6500k lights.
hmmm...well in europe they have 25000k purple cfl's. supposedly they are very good. anyone know anything or ever tried it? if not i think i may try this. heres a link: http://www.stuff-u-like.co.uk/ click on grow lights on the left side of the screen. for some reason i couldnt link to that page.
Yes, 6500k is optimal for vegging. It depends on the full spectrum of the light, however. No light puts out exactly only 6500k, it produces a range of light-colors that center around the reported number. But basically any MH, CFL, or fluoro rated at a 6500k color temp is right for vegging.
i did some seaching on this subject because no one seems to know anything about bulbs with a higher kelvin that 6500k. here is what ive found. marijuana grows best at the wavelengths of 440nm (blue) and 670nm (red). anything else is basically disreguared. most of you probably know this. looking at calculations done on http://www.colorpro.com/info/data/daylites.html i have found some interesting data. the radiant power of 62 daylights from 4000k to 25000k were calculated between the wavelengths of 300-830nm. at the bottom of the website you can see them all. ill list some here: 6500k 440nm: 103 670nm: 78.15 10000k 440nm: 150.7 670nm: 81.2 20000k 440nm: 208 670nm: 96 25000k (purple) 440nm: 220.5 670nm: 101.1 From this graph you can see that 6500k is about 100 at 440nm where as the 20000k is double that at about 200 relative radiant power. From the information i have found, the higher the kelvin temp the stronger power output in the wavelengths need to grow mj...especially the 440nm (blue) which is good for strong, compact vegging. Let me know what you guys think. Seems to me that the only reason people do not know about this or have to tried this is due to lack of info and lack of production of higher kelvin bulbs. i will be trying this out with a 200 watt 25000k cfl. i guess we will see.
Interesting. I would like to see how they grow. Send me a link if you start a grow journal with these.
sounds cool I read up on those and can't find out how many lumens those purple CFL's have, is the same as a normal CFL?
heres a link to the developers site.(i think) http://www.nlitesusa.com/products/compact/index.php anyways they have all the specs for the lights on there. they are about the same lumen output as 6500k cfls. between 8000 to 23000 lumens depending on model (125-300 watt)