It's 2019, What IS the Known OPTIMAL Spectrum for Resin/Terpene Rich Cannabis?

If you could customize an LED grow light for cannabis, what spectrum and dimming options would produce the greatest resin and terpene production? I've been reading and watching as much about LEDs as I can, but I still haven't a clue about spectrum and resin.

UV levels the same as 5k feet above sea level? Higher? Lower?
How much Infra-Red are the top of the line lights using, how does this effect terpene/resin production?
What discrete spectrums and at what power?
What else should I be researching?

Is there someone talking about this subject I have not run across yet? Do you know any data archives I can mine for this info? Greatly appreciate any threads to follow here.

I looked into this very subject a few years ago and have some papers on
the application.

Was side tracked by life stuff and let is rest.

Fascinating topic that kept my interest until I deemed the project
unable to scale up to larger grows as great genetics flowered under HPS
always seemed to trump the tech behind making average genetics pop with the
LED tech available at the time.

Maybe in a few years I'll look at led's again.

Its 2019, people are still working out they gender let alone optimal photon output for cultivated cannabis.

Blue light is converted into more.. smell.. than red light. Though people just comment on a different taste when a bluer spectrum is used, not a stronger taste.

UV is repeatedly called upon as the resin producer, then falls short of expectations.

Red is a bulking light. Not attributed to either. So less red would lead to more of each. Presuming as much of each was still produced, over that smaller area of bud. Which I can well believe. Any pheno that excels in quality above the rest, almost invariably has a shit yield.

Led grows seem to of shown us that resin isn't related to IR protection as once thought. Or UV protection. Just red and blue grow a plant that naturally makes resin. With nothing we do able to effect the quantity in a way we all accept is true.


There is a real hero on this site that likes resin production. I look forward to their thoughts

Dropped Cat said:

Fascinating topic that kept my interest until I deemed the project
unable to scale up to larger grows as great genetics flowered under HPS
always seemed to trump the tech behind making average genetics pop with the
LED tech available at the time.

Click to expand...

Interesting project, were you specifically chasing cannabinoids, terpenes or both? What was limiting in the LED tech at the time for your project?

Illuminate said:

Its 2019, people are still working out they gender let alone optimal photon output for cultivated cannabis.

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lol Anyone raised properly has zero questions about their gender. At least some people's kids are chasing optimal photon output.

f-e said:

Blue light is converted into more.. smell.. than red light. Though people just comment on a different taste when a bluer spectrum is used, not a stronger taste.

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Terpenes. Is the smell more complex, or simply 'more,' in blue light? Has terpene profile testing shown any direct influence on specific terpenes manipulating very narrow spectrums?

f-e said:

UV is repeatedly called upon as the resin producer, then falls short of expectations.

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I've read up on this a few times myself. The most 'concrete' study was done in 85 I believe? UV exposure, from seed to harvest, produced higher THC levels with higher UV levels. NLD types did better with the extreme altitude UV than WLD types. If I remember correctly.

f-e said:

Red is a bulking light. Not attributed to either. So less red would lead to more of each. Presuming as much of each was still produced, over that smaller area of bud. Which I can well believe. Any pheno that excels in quality above the rest, almost invariably has a shit yield.

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I'm thinking there's a minimum of red required for proper flower structure. Granted, the less surface area grown under the trichomes, the more resin per gram you're going to have.

f-e said:

Led grows seem to of shown us that resin isn't related to IR protection as once thought. Or UV protection. Just red and blue grow a plant that naturally makes resin. With nothing we do able to effect the quantity in a way we all accept is true.

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I've grown under SILs and they have little to no IR, as far as I know. Does cannabis require a minimum for anything? I personally don't see differences under the few SIL runs I have under my belt. My awareness is still very low on this subject, so I'm sure I missed something. lol

f-e said:

There is a real hero on this site that likes resin production. I look forward to their thoughts

Click to expand...

Me too

Greatly appreciate the insights and thoughts everyone. I'm still looking for any info on specific wavelengths and their effects. You can be sure I'll post any links I find here, it's easier for me to keep track this way. lol

Keep BEing Awesome!

You might have missed this in the lighting science thread, I think its what your looking for showing blue creates more cannabinoids. Using only blue light during the last like week of flower supposedly boosts cannabinoid content according to lumigrow, i dont think its worth it personally. As has been mentioned Red in the 662nm range promotes producing bud and blue in the 430nm range promotes cannabinoid and leaf production, stretching is caused by infra red. The ratio/balance between the 3 effect the type of growth you get.

I havent done a controlled side by side to compare UVA/UVB effects on total cannabinoids vs no UVA/UVB treatment so its still in the air.

Spectrum effect on cannabinoid production:

https://www.icmag.com/ic/showpost.php?p=8465808&postcount=19

Ratio Of Red, Blue, Infra red light effect on growth:

https://www.icmag.com/ic/showpost.php?p=8467474&postcount=23

If you wish resin packed plants and best terps then use organics,true soil mixes and made
them highly bioactive with diverse beneficial bacteries life and good quality mycorhiza..

terps are specialy dependant on rich micro life,when soil is enough bioactive then production of terps will be in a way it needs to be... micro life helps plant she achives optimum growth and in that case terps will be more concetrated,more stronger..

plant use terps to repel bugs as its very good known that bugs dont love terpenes
a lot,it fucks with their systhem,except bees that collect propolis that is full of terps..

bees also collect terps to repel bacteries and protect honey from pathogens of all kind..

so if you wish terps keep your plants happy in a healthy and alive medium.. the rest for you will do a microlife..


Its definitly not about light so much dependant how is dependant on microlife and to plants grow whithouth any stress..

Dog Star said:

Its definitly not about light so much dependant how is dependant on microlife and to plants grow whithouth any stress..

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I'm working to keep the thread spectrum specific, thank you for sharing the other information.

Ibechillin, I missed your whole post and the bit in the lighting science thread. I'll be going back over this tomorrow. Thank you!

How much far-red is needed for a 4x4 space of plants? If I can get these on a timer and dimmer I will. Doubtful, but something to ask for anyway.

The research ive done on far red lighting suggests you only need the high far red ratio to simulate the sunset conditions outdoor during the last ~30 minutes of the lights on period for the stretch response.

In the link I attached at the bottom it explains daylight is around a red:far red ratio of 1.15 (15% more red light) to 1.37 (37% more red light). At sunset the red:far red ratio is closer to 0.7 (30% more far red light).

The link explains that by covering greenhouses with blackout tarps before the high far red sunset lighting reaches the plants final height could be reduced up to 25%.

Link to study on red:far red ratio and plant growth:

https://journals.ashs.org/hortsci/view/journals/hortsci/42/7/article-p1609.xml

There is a lot of wishful thinking goes into our ability to detect fuller profiles.

The first thing we need to accept, is that smell and taste are the same experience. The messages take a different route around the brain to the processing center, but we can't separate them. Pinch your nose, pop a jelly bean in your mouth, and behold, it tastes of bugger all. Then let your nose go. Pow! it tastes loads. But wait... you actually smelt it. It tastes no different, if your stuck on the idea of taste buds. So what happened? This test is generally needed to begin deprogramming our expectations.

Now the kicker. Most of us can only separate two tastes at once. We recognise the taste of pizza, because it hits a number of points in our memory map. We may eat pizza and remember a time gone by, where we can picture pizza. We don't get the three tastes of cheese, bread and tomato though. For most of us, we just have enough points in common with memories to know it's pizza.

Some of us are supertasters. We can taste 3 things at once. Without any memory map, we know it's probably pizza because we can isolate the 3 tastes easily. Most of us believe this is us, we can do that, but it's more wishful thinking. Blind tests are needed.

So, with so few of us able to taste 3 things at once, and no memory of having tried a particular thing before, a wider profile offers little comparative gain in taste terms.

I found buds grown with more blue lean towards a greener and more hash like taste. A thicker fuller flavour for sure. But my thoughts of greener and more hash like are straight from my memory map, having expectations and little more to compare to.

You know the best thing about wine is the bottle? It triggers memories that have a greater effect on your taste perception, than the wine does. Stain a white wine red, and experts will rate it totally differently. Talking about dark berry flavours. Move this notion to tuna tins, and people pay silly money without seeing it. People that are normally picky, find a tin can appealing. Like they know what's inside it must be special. Give it a fancy confectionery name, and it's already good weed. Even without seeing it.


I have gone off a little, but I hope to of explained why reports are sketchy. People know they can't tell much other than it's different. With the occasional wine expert thrown in for good measure.


Lab standard results would be nice, but where would you start. Something like a mass spec at least, for looking at results. Leds to target spectrums. What plant? and if we chose sk1, how would the result carry over to a Kush. We are a long way off.

All I have read is that a greater proportion of blue goes towards the smell, than it does of red. My blue tests were adding an additional 150cmh in one corner, and a 150 son in another. I did try a full swap out for MH but it was not comparative, though the failed yield was outstanding

eBay have supertaster test strips.

What flavor is red velvet lol.

Old curtains lol

Doing a mix of 2700K and 5000K right now. With 5 or 6 Cannabis plants.

Light spectrum was chosen because non-Cannabis plants liked it.

Might need 10 different grow set-ups to experiment & answer the question. Sort of like how growers found out that HPS was better than MH for late flowering, and then they developed the Son-Agra, and then the Hortilux Eye.

Good thing I'm snowed in, I have a lot of info to process. lol (perfect timing)

Ibechillin, I'm unable to give you additional rep points right now. lol I've been wanting to get a supertaster test for a while now, f-e. I'm definitely hyper sensitive to taste/smell/touch, but no idea if I can taste 3 different things at once. Very good points, ty.

St. Phatty, do you have flower from a previous run of these genetics under different lighting? I'd be interested in the differences you can detect.

Ive flowered with (2) 1000 watt Horti Blues in a Growzilla Hood over a 4x4 tray...

My yields were down but quality on the final product was noticeable.. still not worth the loss in weight though


side note... I have an associate who's friend has a legal 1000 light grow and they use the new Gavita LEDS ... I know this sounds like BS I dont believe it AT ALL... but he's a big time dude around these parts and he says 4lbs for every 1000 watts of Juice drawn with a huge yielding Wedding Cake pheno that they get 3 lbs a light off of Gavitas HPS 1150w..most other strains 2 a light with the DE... anyways.. dont the Gavita LEDS draw like 630 watts? SO he's using like 4 per 4x8 and drawing the same Juice as 2 DE Gavitas turned all the way up....

Not gonna lie bro... I wanna try it out for myself ... Espresso and 1st bowl of the day rant over....

Gavita says it uses top bin Osram and Samsung led and advanced Philips drivers but doesnt list which ones on the site/brochure specs, and ya they draw 630w on 240v power. The fixtures are almost 4x4 wide at 44 inch x 44 inch so they would be running 2 per 4x8 table. 1260w total pulling 4 pounds ~1.5 grams per watt vs the double ended using 2300w total over the same space yielding 6lbs ~1.2 grams per watt. Totally reasonable yields with a high yielding cut imho. The abundant overlapping light from having rows of them hanging in parralell would help too.

Here is the Gavita 1650e led spectrum:
(no UVB/UVA or Far red but abundant usable red and blue light)



The Fluence Spyderx plus is near the same configuration as they are both 8 led bar fixtures that fit a 4x4 space pulling around 630-650 watts, spectrums are near identical but Gavita has more blue it seems.

Fluence spyderx plus spyder2p spectrum:

Am like those Gavitas 1650 LED... they already prooved its a top notch fixtures
on those Gavita 1000 DE and 750.. you dont hear much their lights goes bad
so i belive that this new entry with LED technology needs to be on par
with quality and renome of this company..

Gavitas are great IMO.. and i wish to buy one to try it..

Duplicate post, so I'll link a nice little California Light Works article...
Using Spectrum Control to "Design" Your Plant - AKA Photomorphogenics

Douglas.Curtis said:

Interesting project, were you specifically chasing cannabinoids, terpenes or both? What was limiting in the LED tech at the time for your project?

Click to expand...

Limiting factor was start up cost, so we went with
industry standard Paralux HPS 1000w fixtures with e ballast
as supplement lighting, double ended bulbs, 92 of them.

Maximizing yield with the cultivars proven for taste.

All crops are sold before the plants hit flower.

Terps are there, no question. Heavy production,
in several greenhouses out west, living soil, organic.

Since LED tech is catching up for high bay grows,
I'm pushing to change over one house to Valoya lights,
as a test run, but won't be cheap.


We'll see.