Is there a benefit to using 4200K CMH in veg?

[bibbles]

Or, is this just sort of a holdover from the MH/HPS switch?

>In our experience, the 13.4% blue light from CMH lamps would be adequate to grow all species without adding supplemental blue light (see spectral output graphs and summary table).

This is what Utah State had to say about the 3100K Philips, which puts out significantly more PAR than any other CMH lamp, including their own 4200K. Obviously, "adequate" doesn't mean ideal, and so perhaps the 4200K still manages to produce better vegetative growth, despite it's lower output? After all, cool white T5 is 24.1% blue, a larger gap than there is to the 4.9% HPS (no data for the 4200K).

I'm not asking if I really need two bulbs, I already have the 4200Ks, and I flower under DE HPS.

GrowersHouse has comparison data here, but it doesn't cover this.

 

[MIMedGrower]

The phillips 3100k kept my veg plants more compact than i really like even compared to a hortilux blue mh 400 or 6500k t-5 flourescents in my veg tent. I dont think i would like even more blue spectrum like the 4200k would have. But i have not tried it.

 

[bibbles]

I just made the move from a 400W induction light (just one 315W at the moment), which was supposedly comparable to a 1000W MH, and everything looks a lot healthier now. TK is still more spindly than I'd like, but they do seem better, despite being further from the light than they really should be (about five feet). Old MAC mother looks good too (three feet), some branches look like they're stretching a bit more, others look like they've got considerably more lateral growth, but all in all this just means more consistency; plus, I didn't start her, and I plan on replacing her ASAP, because she was not very well looked after when young.

So far, I really couldn't be happier, but I did buy the 4200k bulbs prior to asking myself the title question. Ultimately, we're talking about a 10% difference in PAR, which is significant, but it also means that the 4200K lamp really only needs to put out 15% blue light (and it looks like more than that) to do more in that area than the 3100K. This is my first time not having to deal with eight foot ceilings as well, so... a lot of things are changing, and... I guess we'll just have to see?

I've got an extra little 3'x9' nook in my new flower area, so perhaps I'll pick up another three CMH lamps, but this time in 3100K, which may lead to some side-by-side action in veg and/or flower, who knows.

New garden goodness has me occupied for now.