Kelvin effects on Cephalotus? Has there been any testing?

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In the next few weeks I will be ordering a good amount of LEDs for the Cephalotus rack I'm putting together and my first instinct would be to go with LEDs with a daylight range. However, I've read a few posts here and there about people using different ranges and getting better coloration.

That leaves with me with a few questions.

Has anyone done any testing?

If it turns out that there is not any useful information I would be willing to set up some tests. I should have 4-5 shelves and could easily do one daylight, one cool, and one warm. Last time I checked I have enough 'Emu Point Giant' leaves to use that clone as a control.

Thoughts?

 

[amphirion]

I'll go the null here. No difference based on kelvin, only what is more aesthetically pleasing to the eye. However, Kelvin could be dependent upon spectrum output which does matter.

 

[yuusui]

At the last meeting of the Upper Midwest Carnivorous Plant Society, we looked and did some testing of LED plant lights. You can see the results here.

http://umcps.net/

I hope that helps you some.

 

[rcl27]

Yuusui's article sums it up quite nicely. I was actually surprised how much of a difference I saw from moving my ceph next to a 40 watt CFL. It spent roughly 3 weeks in the position and went from this:



To this:



I am using a Badboy fixture up top with 4 6500K T5HO's, a 40 watt 2700K CFL on the side, a 100 watt 2700K CFL in the front, and a single 2700K T8 along the back. The Cephalotus was originally about 14"from the T5's and roughly in the middle so wasn't receiving muck warm light. In the new position it was about 6" from the T5's and about 6" from the 40watt CFL.

I think it's funny that you can tell what side the warm light was on. The other side is ever redder and the newer growth below on the main plant is still quite green. When I want to add color I usually move the plants to the front of the tank with that 100watt CFL. My established pings go crazy with all that red spectrum.

Best,
Cody Lawson

 

[mobile]

Unfortunately kelvin doesn't tell the whole story, rather you need to look at spectral distribution. Indeed, the spectral distribution of same colour temperature from different manufacturers can vary. Personally I find better results under warmer temperature LEDs, which typically have more power in the red end of the spectrum, though this is an observation and not based on any controlled experiment.