Kelvin vs PAR

[akazzer]

I was hoping there might be some folks on here that could help define just how much value Kelvin has when rating a lamp for plant growth.

I just read an online article which had a chart that showed Kelvin is only a reference to color that the eye can see and should not be relied on for the plants UV and IR needs. This makes me wonder just how much value, if any, to give a Kelvin rating relative to my plants PAR wavelengths needs and if so I was wondering how much?

I've seen the new Bi-Spectrum lamps, that emit 5K+ white light and produce light in the IR range outside visible light for PAR, I'm just curious if anyone out there has any science to support how important is the red color I'm seeing to the plants needs or is all about pushing more lamp sales of 'separate spectrum's'?

 

[akazzer]

I see that LED mfg don't post a Kelvin temp rating because they target the narrow bands within the PAR ranges thereby getting a better yield from the use of those precise bandwidths. Seems PAR logical but they (LED) have to produce enough YPF energy as well to satisfy the plants absorption requirements.

If PAR quality and Photon quantity matter more to plants why is there so much marketing attention given to the visible Kelvin rating of some of these lamps?






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