Canopy Penetration for HID and LED lamps.. oh, and perhaps distance from canopy

j.diesel_NY

In Bloom
Sup grow fam. I want to feel like I know what I'm talking about and figure, the best way to get there is to open up a discussion on it.
CMH vs HPS vs LED canopy penetration. What is the average, or ideal canopy depth that you've come to accept in your grows?
Here's about what I've really experienced and learned from growing. I started with CMH in open fin type hoods from an HPS lamp and adapter for the bulb, with a separate ballast wired outside of the tent. I figured;

315w CMH gets you a 3x3 pad pretty well from about 30-40" off the canopy, and gets about 16-18" in depending on the strain and your pruning preference.
... doing the math on that you have 13.5 cubic feet of bud canopy where you're growing the fruits of all our desire.
2x 315w CMH don't exactly get you a 6x6, it's more like 3x6 at best. Same everything else, that's 27 cubic feet, but your canopy penetration is lower by maximizing the spread, so consider a 16" vs 18" penetration before it's larf. Now you've dropped to 24 cubic feet of love nuggets.

1000w HPS gets you a 5'x5' with good penetration which gets you 50 cubic feet of usable bud pad area. 5'x5'x24" = 50 cubic feet. WoW!.
600w HPS is unfortunately half of that, from what I can tell. So however you cut the canopy penetration up with a selection of hoods, you're at 25 again, or, more or less the same as a pair of CMH 315's, but we all know there's a difference in the bud coming out of a 600w HPS vs a tent rocking 2x 315's right??? HPS is going to finish up a little heavier, the CMH tent is going to be more colorful perhaps, more terpene production, but a little smaller buds overall. No?

LEDs. Welp, to cut out lensed red/blues for now let's say it's 2023 and we're all looking at a 1k equivalent 750w +-5% power rack that says it can flower a 5x5. Distance off canopy varying per model and manufacturer, but let's say you're adhering to manufacturer best practices...
Can that thing push 24" into that 5x5 canopy? Or are you only pushing down a good 12-16"?
I've not grown with one yet, so I can't really say. I feel like the spectrum of pure white wastes a LOT in the green spectrum (which is reflected off when you look at the color of your leaves), and doesn't give the penetration. Now yes, it also has less of a hot spot, however, are you able to push light down into the canopy is, I guess, what I'm trying to understand.
14" canopy penetration = 29 cubic feet and I smell scrogg, might as well run 2x 315's for a power save.
18" canopy penetration = 37.5 cubic feet, and now we're talking.
24" canopy penetration = and we're back to 50 cubic feet of fresh funk

(your gram per watt is your personal business, based on organic vs salty, strain selection, seed/clone, skill level, veg time, etc... not interested in whipping out anyones anything and measuring length or girth)

What have the growmies been able to realize in their grows?

Right now I've got these two tents running:
4x4 tent, lamps 40" off the canopy in week 2 flower;
600w HPS on a 600w ballast
+
315w CMH with a 3100K bulb


4x4 tent, lamps at 36" off the canopy in week 3 flower;
1000w HPS on a 600w ballast
+
150w MarsHydro LED panel TS1000

And as an aside, I really do feel like the 1000w HPS bulb on a 600w ballast is the fucking way to squeeze out the spread and throw of 600w by underpowering a 1000w bulb. Am I thinking this through backwards? Should I get better off running a standard 600w bulb/hood? I'll be honest this was some cheapassery and I was just accepting gifts to get my grow off the ground.
 

Badmofo529

In Bloom
I feel like the spectrum of pure white wastes a LOT in the green spectrum (which is reflected off when you look at the color of your leaves), and doesn't give the penetration
Green actually penetrates through the leaves better than anything but far red, Dr Bugbee can explain it better than I can lol


In my experience you can usually count on 18-24" of good canopy under LEDs, depending on strain and how well managed the canopy is. Little less for some strains or if it's a fuckin jungle, little more for some with good space around the colas.

In all honesty hps and LEDs are pretty equivalent anymore (although LEDs will continue to improve, and I doubt much money is being thrown into new hps bulb tech), but the power savings of led adds up pretty quick, especially if your using air conditioning, and/or live somewhere where power is expensive.

They all grow good weed as long as you do your part.
 
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j.diesel_NY

In Bloom
Green actually penetrates through the leaves better than anything but far red, Dr Bugbee can explain it better than I can lol


In my experience you can usually count on 18-24" of good canopy under LEDs, depending on strain and how well managed the canopy is. Little less for some strains or if it's a fuckin jungle, little more for some with good space around the colas.

In all honesty hps and LEDs are pretty equivalent anymore (although LEDs will continue to improve, and I doubt much money is being thrown into new hps bulb tech), but the power savings of led adds up pretty quick, especially if your using air conditioning, and/or live somewhere where power is expensive.

They all grow good weed as long as you do your part.

Yo that was amazing! Thank you for sharing that one with me! Seems like if power isn't an issue, these boys running HPS - MH - HPS - MH rows are on to something. But, if you have only a tent and a reasonable budget, LEDs are great! I like your takeaway that basically they all grow good weed if you do your part. The slide that got me was plant shape vs yield!

DUDE THANK YOU!
 

j.diesel_NY

In Bloom
Green actually penetrates through the leaves better than anything but far red, Dr Bugbee can explain it better than I can lol


In my experience you can usually count on 18-24" of good canopy under LEDs, depending on strain and how well managed the canopy is. Little less for some strains or if it's a fuckin jungle, little more for some with good space around the colas.

In all honesty hps and LEDs are pretty equivalent anymore (although LEDs will continue to improve, and I doubt much money is being thrown into new hps bulb tech), but the power savings of led adds up pretty quick, especially if your using air conditioning, and/or live somewhere where power is expensive.

They all grow good weed as long as you do your part.

OK so here's what I've learned. Green light is actually an amazing part of the photosynthesis process. Anyone notice KindLED leading the charge in the under-canopy lighting and supplemental side lighting? Well here's why.
I was accidentally using their 80w light bar for a veg overflow and over the course of a few months lost track of what I had originally purchased it for (flower spectrum) which was for the last week finish to get the frost and final squeeze under a low-light setting, and hitting them with cold water (torture tactic). So I had plants vegging completely used to a flower spectrum lamp with a real lack of green light -- which is what you get from those white LEDs -- but there are very few in the KindLED that I was using... The flower spectrum has very few of these white diodes, but the veg spectrum of KindLED has many more... the one I'm *not using.

I toss these plants under a CMH and it was like taking an un-hardened sprout outside with no graduation or hardening-off. They basically started to die. I had 2x Head Smog by Katsu in 1g cloth pots and within about 10 days nearly lost them. The clone of the same generation under the KindLED the whole time was THRIVING! Literally more new growth than the transplanted ones in 1g's. So out of desperation I placed them back under the reds and blues (KindLED bar) and within about 3 days they started bouncing back and showing new growth.

So I took a picture of them (below) and you can see the lighter colored two plants at the top of the pic -- that's them. Day 1 they were 5x worse. And what it literally looks like to me is a sunburn. As I learned from Dr. Bugbee is that the green penetrates STRAIGHT THROUGH the entire leave very effectively, whereas red and blue photons do not. The red/blues hit the top layer of the leaf and create photosynthesis really well, and cause the leaf to "puff up" a little, & get very rich in color as you can notice in the larger dark colored plants in the lower part of the pic... but don't penetrate at all.

THAT'S WHY KINDLED IS PUSHING THOSE UNDER CANOPY AND SUPPLEMENTAL LIGHT BARS!

So what did we learn?

Red promotes stretch / Blue inhibits stretch -- NEITHER PENETRATE THE CANOPY WELL.
Different spectrums cause different plant shape but produce the same dry weight at time of harvest, per a controlled test with the same set of clones in different lighting conditions.

Green is amazing a canopy penetration. Lack of green causes plants to become susceptible to light shock if you add it in large percentages without graduation.
You can reduce the green spectrum as a plant matures & as it transitions to flower and finishes.
You can not however add MORE green as the plant matures, at least not suddenly, or you can actually burn your plants with green photons. Light shock.

I'm sure there's some UVA/UVB in a CMH bulb whereas there's little to none in that KindLED lamp.... and according to Dr. Bugbee a plant will start to produce a natural "sunscreen" from too much UVA/UVB and cause it to reduce or even stop photosynthesizing... BUT -- I really think it's the green photons that were screaming straight through the leaf, in combination with higher PAR and higher percentages of green. That's what I think sent my poor Head Smog into shock, a real bad one. I almost lost them.

Now I know now that;
running a CMH or LED lamp right next to an HPS in flower, is good in a tent because it can help to reduce the stretch AND bring out some cool colorations
add CMH/LED along side HPS to reduce "stretch" in first 3 weeks of flower
eliminate CMH/LED along side HPS to increase "stretch" in first 3 weeks of flower
reducing HPS and finishing with strong greens in a white LED or CMH (last 5-9 days) can really help to bring out mad good color by putting a tan on the plants

I hope you growmies find this rant useful. Thoughts??


20230331_104852.jpg
 
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Dino Party

💩🔥 💩🔥 💩🔥
OK so here's what I've learned. Green light is actually an amazing part of the photosynthesis process. Anyone notice KindLED leading the charge in the under-canopy lighting and supplemental side lighting? Well here's why.
I was accidentally using their 80w light bar for a veg overflow and over the course of a few months lost track of what I had originally purchased it for (flower spectrum) which was for the last week finish to get the frost and final squeeze under a low-light setting, and hitting them with cold water (torture tactic). So I had plants vegging completely used to a flower spectrum lamp with a real lack of green light -- which is what you get from those white LEDs -- but there are very few in the KindLED that I was using... The flower spectrum has very few of these white diodes, but the veg spectrum of KindLED has many more... the one I'm *not using.

I toss these plants under a CMH and it was like taking an un-hardened sprout outside with no graduation or hardening-off. They basically started to die. I had 2x Head Smog by Katsu in 1g cloth pots and within about 10 days nearly lost them. The clone of the same generation under the KindLED the whole time was THRIVING! Literally more new growth than the transplanted ones in 1g's. So out of desperation I placed them back under the reds and blues (KindLED bar) and within about 3 days they started bouncing back and showing new growth.

So I took a picture of them (below) and you can see the lighter colored two plants at the top of the pic -- that's them. Day 1 they were 5x worse. And what it literally looks like to me is a sunburn. As I learned from Dr. Bugbee is that the green penetrates STRAIGHT THROUGH the entire leave very effectively, whereas red and blue photons do not. The red/blues hit the top layer of the leaf and create photosynthesis really well, and cause the leaf to "puff up" a little, & get very rich in color as you can notice in the larger dark colored plants in the lower part of the pic... but don't penetrate at all.

THAT'S WHY KINDLED IS PUSHING THOSE UNDER CANOPY AND SUPPLEMENTAL LIGHT BARS!

So what did we learn?

Red promotes stretch / Blue inhibits stretch -- NEITHER PENETRATE THE CANOPY WELL.
Different spectrums cause different plant shape but produce the same dry weight at time of harvest, per a controlled test with the same set of clones in different lighting conditions.

Green is amazing a canopy penetration. Lack of green causes plants to become susceptible to light shock if you add it in large percentages without graduation.
You can reduce the green spectrum as a plant matures & as it transitions to flower and finishes.
You can not however add MORE green as the plant matures, at least not suddenly, or you can actually burn your plants with green photons. Light shock.

I'm sure there's some UVA/UVB in a CMH bulb whereas there's little to none in that KindLED lamp.... and according to Dr. Bugbee a plant will start to produce a natural "sunscreen" from too much UVA/UVB and cause it to reduce or even stop photosynthesizing... BUT -- I really think it's the green photons that were screaming straight through the leaf, in combination with higher PAR and higher percentages of green. That's what I think sent my poor Head Smog into shock, a real bad one. I almost lost them.

Now I know now that;
running a CMH or LED lamp right next to an HPS in flower, is good in a tent because it can help to reduce the stretch AND bring out some cool colorations
add CMH/LED along side HPS to reduce "stretch" in first 3 weeks of flower
eliminate CMH/LED along side HPS to increase "stretch" in first 3 weeks of flower
reducing HPS and finishing with strong greens in a white LED or CMH (last 5-9 days) can really help to bring out mad good color by putting a tan on the plants

I hope you growmies find this rant useful. Thoughts??


View attachment 162953
Just curious here, what is your definition of cold water? I thought my water I was giving my plants was extremely cold, at 65 degrees, but reading has me thinking thats actually pretty spot on and where I want to be at. Thats just opening up both spigots of the slop sink to fill the buckets, the hot water tends to come out slower there. I was super surprised because I thought since it was cold to the touch it would be cold for the roots, but apparently not!

I think, if anything, you'll extend the life of your bulb more by running a 600w on your 600w ballast. I believe I read before that underpowering a light will degrade it quicker, but I could be remembering that wrong. But like, I think you want them to ideally be running at near what they were designed to be run at for max effeciency.

I'm running 2 HID ballasts in my veg area right now, one HPS and one MH bulb. for the very exact, sciencey reason of thats what I had. The spectrums kinda blend together and plants get moved around a lot so I'm not noticing one side doing anything the other is not. But, the dope thing about HID is the free heat they provide, if you want it and can use it. I dont gotta run anyting other than the lights and a fan in there. HID is good shit. Okay this bud is kicking in and i'm just rambling now. Great thread, will be subbed in for more.
 

j.diesel_NY

In Bloom
Hey what's up Dino, for the cold water I'd say if it's more than 10 degrees F below the current root temperature that qualifies as cold. I'll ramp it up to straight ice water in that last watering to help them wrap things up even. I've packed the top of a plant with ice more than once to send it the the old gong show hook that we're done here.

Also, freely exchange MH with LED or CMH in the above stoned rant (sheesh, talk about bud kicking in wowza). Any LED with a "white" glow to it has sufficient greens to balance the reds/blues. Unless we're talking the old school reds/blues of what LEDs used to be. That doesn't count in this discussion. The MH's, CMH's, LED's that are white all balance off the HPS golden glow just enough to manipulate the structure and shape of a plant.

Really what I learned in this exploration is that you as a grower have the ability to manipulate growth the way you want using different spectrums at different times. Additionaly, light intensity &/or distance from canopy can be used to either "slow grow" or "accelerate" your garden to meet certain time and space constraints.
E.g. using HPS in veg to stretch things out so that plants are big enough to flower, or ramping up the blues in the first 3 of flower if you had to keep plants in veg for too long, and now they're getting too big and a major stretch would push plants through the roof of your tent.
Increasing canopy distance and increasing white/green light to its fullest (think 6000K CMH bulb) for maximizing a finishing under a low PAR to bring out maximum terps, colors, and weight at the end all the way down into the canopy is very effective. These are all great tidbits and I hope it's been a good read for everyone.

Cheers!
 

Skunky Dunk Farms

Cannabinoid Receptor
Howdy @j.diesel_NY , good investigative work!
I just thought I'd throw my 2 cents worth in.
I started growing when only l8ghts available were T-12 fluorescents. Around '69-'70.
The 1,000 and 1,500 watt MH came out near mid 70's,i grabed onto a couple 1,000s and got my start at productive plants.
In So. Cal. most strains were either from down south and a few from the east. That's about the time I saw my first Thai sticks.
Anyhow, as time went on the 400's and 600's started to appear and i began using those in the MH and HPS configuration and was really beginning to like gardening indoors, I was still doing outside gorilla sites in the hills.
Rock hard Boulder buds all around.
Then then new millennium arrived wirh it's fancy new offerings.
So, after about 30 years of running one sort of HID or another , with great success, I was persuaded to take a look at the upcoming led sensation. But I was also discovering the new CMH prospects.
And today, with very good results I have over my 3x8 canopy 1, 244 Samy q panel then a pair of 315 w CMH's, then another 244 q board, 2 more 315w CMH's and a final 244 q board.
This combo has givin me the best results over all for density of flower,light penetration and a varied spectrum of light that plants seem to love. My harvests are massive.
Anywho, just my take on the lighting possibilities and the use of multi platform units.
I'm a light whore, I run my lights down, on the plants, at flip it's not unusual to go in my room after flip and find a top up in a reflector. I keep the leds about 15" and the CMH's around 18" and just make sure the plants have enough water and nutes to "use" all that light.
Have fun with your decisions.
 

j.diesel_NY

In Bloom
Howdy @j.diesel_NY , good investigative work!
I just thought I'd throw my 2 cents worth in.
I started growing when only l8ghts available were T-12 fluorescents. Around '69-'70.
The 1,000 and 1,500 watt MH came out near mid 70's,i grabed onto a couple 1,000s and got my start at productive plants.
In So. Cal. most strains were either from down south and a few from the east. That's about the time I saw my first Thai sticks.
Anyhow, as time went on the 400's and 600's started to appear and i began using those in the MH and HPS configuration and was really beginning to like gardening indoors, I was still doing outside gorilla sites in the hills.
Rock hard Boulder buds all around.
Then then new millennium arrived wirh it's fancy new offerings.
So, after about 30 years of running one sort of HID or another , with great success, I was persuaded to take a look at the upcoming led sensation. But I was also discovering the new CMH prospects.
And today, with very good results I have over my 3x8 canopy 1, 244 Samy q panel then a pair of 315 w CMH's, then another 244 q board, 2 more 315w CMH's and a final 244 q board.
This combo has givin me the best results over all for density of flower,light penetration and a varied spectrum of light that plants seem to love. My harvests are massive.
Anywho, just my take on the lighting possibilities and the use of multi platform units.
I'm a light whore, I run my lights down, on the plants, at flip it's not unusual to go in my room after flip and find a top up in a reflector. I keep the leds about 15" and the CMH's around 18" and just make sure the plants have enough water and nutes to "use" all that light.
Have fun with your decisions.
Nice man. My first first grow as a teenager was under those florescent fixtures too. Wow what journey. I definitely respect the time you have invested in growing and know that your decisions are all results driven. Likewise I'm mixing it up still from run to run, seeing the outputs, learning more about light spectrum, nutrition, disease, genetics, etc. etc. etc. all as much as I can as fast as I can, and so far seeing some fairly good results (and having loads of fun). I like the combo of CMH/LED. I've heard that mix produces the best results from another person that has claimed to of tried more or less every possible combo of lamps over the years. They said the same thing about alternating the CMH and LEDs. Another grower up in Canada that I'm testing beans for has an interesting array of lensed reds/blues way off in the corners of his room shooting at 45 degree angles across the room, with a CMH up at the top center, and a side-mounted light bar for cross-canopy penetration. He's running an entire room of like 15-18 plants on like 1800 total watts. It's crazy what happens with good canopy penetration. I think the most frustrating part about the LEDs to me is the lack of scatter. HPS goes EVERYWHERE and you have to have a tent to catch all the ricochets of photons. LEDS seems to be the opposite if that makes sense. The non-lensed gives a little better spread but if you leave the canopy by much your PAR goes in the toilet. Then lensed are good at distance from canopy, but like lasers.
Anyways thanks for the reply and the good info Skunky!
 
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