I think the high CRI lights are a great supplement to the Rspecs I’m using in flowering, really fills out the spectrum and the plants seem to love it, they’ve been extremely “perky” ever since being put under these lights.
But there are still some issues that I’m looking out for before making a final determination.
First one I was looking for was - will the plants just keep stretching in flowering - and the answer is no, they stretched as expected for first 3 weeks or so and then stopped as they should.
Other things I’m looking for are near harvest time:
Any abnormal foxtailing?
Do plants finish up in the normal time frame?
Are trichs developing as normal?
Any increase in smell (or taste after harvest)? These girls smell wonderful already, such a nice sweet fruity fragrance every time I open the tent, more smell could mean more terps.
I’m very happy with what I’m seeing so far from these high CRi lights used as a supplement to the Rspecs but really need to wait til the end to make sure no unexpected issues show up.
I definitely want to see what you think about the high cri. HLG is the only light bar I found so, the rest are strips. Hope they show good results. @dbrn32 , do you know of any other high cri light bars for horticulture use?
Cutter electronics. The color rendering index is just a reference point of how colors appear under a given light to their natural state. A light could have a very low or high cri and be great at growing weed, or could be either and be horrible at growing weed. Incandescent and halogen have very high cri, but are horrible at growing weed. And high pressure sodium has very low cri, but is very good at growing weed.
It just so happens that most of the modern high cri led options fit both categories. Applying phosphor over violet led instead of blue has opened up the wider and more even spectral distribution, but has done so at cost of efficiency. So depending on intent could be great option or maybe not so great. Mattybear, Covertgrower, and I all have lights built with 90+ cri leds. They aren’t identical to what hlg is offering, but they do pretty good.
Awesome! I’m going to give them all a little bit tomorrow! I know for a fact it drives the ppm up. I will double check for sure. Thanks, I appreciate your response!
@HollyHo 15mls to a gallon or less ? Fill the drain pan first , than pour into from top ? Thank me later but wait until they drink it from bottom blessings and keep it clean and green !
I guess my question comes back to canopy penetration, and the use of spectrum 500nm to 600nm range. The high cri is causing your brain to percieve richer color depth of the greens, but is the canopy penetrating power actually increasing, and if so, is that extra photon range actually increasing photosynthesis or another beneficial growth factor?
Good morning Hellraiser. I’m starting week 7 since flip today. Judging by these pictures, would yo think I’m safe starting water only in the next few days? Trichome shots are in order from Top, Middle to Bottom of canopy. Coco and perlite with Jacks 321 and Tribus.
Thanks! I’m honestly just trying to get those beautiful fall colors to pop. Went through this grow mostly by the seat of my pants. First coco run and first time using Jacks. By far the healthiest plant I’ve grown to date.
These look great! But only 6 weeks of flower? How long do you plan to flush? 2 weeks like hell? If so, I’d give them another week of feeding at least. Just my opinion! Good job so far!
That was my idea. Today starts week 7 but the breeder didn’t specify an approximate finish time on these seeds. My Tap water floats between 225ppm-275ppm so I figured I’d run that for a week and see where she’s at and if needed, I’ll run out and grab a few gallons of RO to drop runoff ppm more over the last week.
You run full strength from the beginning? I just started using jacks. Nothing else. My plants were having a hard time w it so I had to drop ppm a little. Just curious how you’re running it. Thanks!
“Starts week 7” so it’s finished 6 weeks. I’ve learned it doesn’t hurt any of them to go at least 9 just my opinion tho as I stated. I have been bit by the anxiety bug before and wished I had let it go just a liiiittttle longer. One week won’t hurt. Like the other guy said, there’s still quite a bit of clear. Especially on those lower buds. Let it go and you won’t be sorry.
I’ve done full strength the whole time. Then at about week 3 of flower I really noticed dark green shiny fans with clawed tips so I backed off the part B to an even 2g per gal, Epsom to 1g per gal and increased part A to 4g per gallon. I’ve also been monitoring the DLI with it. Pushed to 45 dli the 2nd half of the week before flip and gradually made it to 60dli by the 2nd week after flip and just dropped it back to 45 last night as lights came on. And plan on finishing at 45.
This is multi faceted question. When you are discussing photon intensity in terms of photons collectively this is ppf and takes no account of photosynthetic efficiency of specific wavelengths. Ypf (yeild photon flux) would be the measure of photosynthetic efficiency of each wavelength.
If you want to speak on individual per wavelength basis, the graph below shows the relative quantum efficiency per band.
This is exactly what brought us to early blurple led fixtures. Without going too far down the rabbit hole, the performance of said fixtures compared to something like even a first generation quantum board should say everything it needs to about solely targeting ypf over total ppf. Wavelengths outside of blue and red may not be the most photosynthetically active, but they are still responsible for certain plant processes and responses. The next chart shows how ypf and McCree action study data would be blended
Does it look familiar? This is basis for pretty much every “high end” fixture or knock off currently available. But going back to ypf is the reason you see 660nm added to base phosphor coated leds.
The chart below us from bridgelux and shows their 80cri phosphor above and 90cri phosphor below. You may have to look close, but anything 4000k and warmer will show peak around 600nm on 80cri. If you move to 90 cri chart you can see that those same peaks shift over about 630nm. Which helps in terms of ypf, but in most documented cases the total amount off ppf at given power goes down. In short, it’s more difficult to get the cleaner looking or more photosynthetically efficient light out of the leds. To the best of my knowledge, the higher the cri gets the less photon efficient they become. Hlg pretty much tells you this in their advertising, by way of saying “not suitable for main flowering lamp”. This is because they know it will take a lot of their high cri light to produce good grow results and they’re not going to stake their reputation otherwise.
Nichia and cree have had 5000k 98 cri that has basically matched sunlight spectrum within par region for quite some time. Cutter has offered the nichia for at least 3 years to my knowledge. Imo there is a reason they hadn’t already taken over the market. That reason is most likely because the ppf/watt is too low to make up for the performance of the broad/even spectrum. And has pretty much left its appeal to those who are strong believers that the sunlight spectrum is better than artificially created light spectrum. To get much more than that you would probably need to get with someone like greengene or growmau5 who’s job is to make these more targeted breakdowns.
just my opinion tho as I stated. I have been bit by the anxiety bug before and wished I had let it go just a liiiittttle longer. One week won’t hurt. Like the other guy said, there’s still quite a bit of clear. Especially on those lower buds. Let it go and you won’t be sorry.
