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When comparing natural sunlight to LED grow lights, which one truly outperforms the other?

JanKowalski

Well-known member
You can't beat his majesty, the Sun. More than 4 milliard years ruling our planet ( Probably more ) Sun it's life.
If you're lucky, you don't neither need a greenhouse. No competition at all IMO.
 

Rocket Soul

Well-known member
Can't have one without the other. As is already said normal greenhouse materials block all UV.
If you can do a modded design at least you can let in some sun during midday. I feel you on the rott, but here its usually quite sunny all the way into october. Seems like the way climate change has worked out in our region is that all seasons just arrive and stay a little later. We had our spring rains in may/june this year and outdoor is doable thru october usually.
 

Rocket Soul

Well-known member
It’s not the intensity, it’s that indoor lighting is peak intensity for all 12 hours of daylight. There is no dawn or dusk period of lowered intensity. View attachment 19046737
Thx for the maps:)
I get that but where i am (spain) we have approx 8 hours of about twice the lux of a standard growtent during peak flower season. And sunlight lux have more photons than grow lights, its more weighted towards the red and blue ends than most lights. Maybe we have less clouds and of course you could run any tent at extreme light levels but i doubt it would be growable; plants seem to be able to handle more photons from the sun than growlights. I just dont know how to grow in a 2000ppfd led tent, but outdoor seems to work. In any case not worth arguing about; i think the real killer with sunlight is the long season and spectrum.
 

Brother Nature

Well-known member
Can't have one without the other. As is already said normal greenhouse materials block all UV.
This is not really true these days, there are many different types of glass and plastic used in greenhouse production, most of which does now allow uv rays through. I have even seen them advertised in home use greenhouses sold at local hardware stores. The material doesn’t last as long as the traditional plastics used in the cheaper greenhouses though.

 

Lester Beans

Frequent Flyer
Veteran
There is no replacement for displacement! The Sun!

For indoors the finest herbs are grown under HPS. I tried LED and it just does not produce the same quality. Back to HPS.
 

yoss33

Well-known member
Veteran
The optimum would probably be a sun powered greenhouse where the sunlight is extended with leds. And ofc featuring fully controlled environment.
If costs don't matter, and you comparing simple outdoor to indoor leds, leds will probably win, because the environment is much more stable, no pests, and the light while being less powerful, it's always there without variation and always given at the needed strenght.
I think you actually described well why outdoors is better :) Exactly because of the stable environment indoors with no pests and no variation in light and temperature, the plants are not stimulated to "defend" (inc. with cannabinoids and terpenes) against harsh and variable conditions. Proper outdoors triggers all defending mechanisms without damaging the plants (much). Of course, outdoors conditions are harder to control and so there's more risk, esp. where conditions are not optimal for cannabis, so you might actually get a better product indoors. But proper outdoors will continue to be the best.
Regarding light, the sun is moving (shining from different, almost opposite directions), has variable (daily and throughout the season) spectrum and intensity, has UV and lots of heating infra-reds. It's a very different and much more complex light than the artificial lights. Yes, simple lights also grow plants. But the result is different.
 

PH donner

Active member
you're forgetting another advantage of growing indoors!
An outdoor plant always has more leaves than the same genetics grown indoors.
I have also flowered all my indoor genetics from the past 25 years outdoors by darkening them because I am in the Netherlands.

From this I also experienced that plants that enjoyed the sun outside were stronger with a different buzz
 

Rocket Soul

Well-known member
you're forgetting another advantage of growing indoors!
An outdoor plant always has more leaves than the same genetics grown indoors.
I have also flowered all my indoor genetics from the past 25 years outdoors by darkening them because I am in the Netherlands.

From this I also experienced that plants that enjoyed the sun outside were stronger with a different buzz
Youre likely referring to indoor hps vrs outdoor: this has nothing to do with the place but the spectrum. More blue in sunlight (5600k) means more leaf, top cannopy behavior. HPS is less leafy of course but youd be blind if you havent seen some pretty leafy 5000k based ledplants around.
Blue response is
- shorter internodes
- more and smaller leafs
- stomata aperture - increased transpiration
- inhibition of cell expansion
- root stimulation.

Maybe ive missed one, not sure.
 

PH donner

Active member
Youre likely referring to indoor hps vrs outdoor: this has nothing to do with the place but the spectrum. More blue in sunlight (5600k) means more leaf, top cannopy behavior. HPS is less leafy of course but youd be blind if you havent seen some pretty leafy 5000k based ledplants around.
Blue response is
- shorter internodes
- more and smaller leafs
- stomata aperture - increased transpiration
- inhibition of cell expansion
- root stimulation.

Maybe ive missed one, not sure.

I have only been growing LED for a year with the MH 8bar6500. The times before HPS 1000watt Gavita. These are just my humble experiences with the genetics I have worked with...and smoked
You should try it yourself and then check the numbers to see if that is correct.
With my LED at full power that the plant can handle, the internodes are much shorter than when I am at low power. I mean you can go in any direction with those numbers
 

Rocket Soul

Well-known member
I have only been growing LED for a year with the MH 8bar6500. The times before HPS 1000watt Gavita. These are just my humble experiences with the genetics I have worked with...and smoked
You should try it yourself and then check the numbers to see if that is correct.
With my LED at full power that the plant can handle, the internodes are much shorter than when I am at low power. I mean you can go in any direction with those numbers
Yes, inter nodes are not only depending on blue content, intensity matters a lot aswell. I actually have experience of this: in our grow we only use leds built by me, going from 5000k white base (in late veg so hard to say how it looks in flower) to very red heavy +60% red flower leds. When we take our clones from straight 3000k 80cri white to the late veg lights you defo see a slight shortening of growth. Leaf size about the same but those extra blue light also have a bit of red 660 in them, which tend to grow bigger leaves. Hypothesis,: When the plant sees a lot of red and blue it feels wow, perfect conditions for growing as much as i can and has a very nice growth behavior. But you need some green aswell, im not calling for blurple



Do you find your Mars hydro leafier than HPS? How would it compare to outdoors? Genuine interest :)
 
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PH donner

Active member
Do you find your Mars hydro leafier than HPS? How would it compare to outdoors? Genuine interest :)

Unfortunately I can no longer make that comparison because I am working with other genetics again and have only been working with Led for a year now. I have noticed that outdoor weed is simply stronger with a different buzz and hiccup than the same genetics grown indoors. The indoor plant wins in terms of appearance, which is of course also very important for the presentation of the product.
 

Rocket Soul

Well-known member
Unfortunately I can no longer make that comparison because I am working with other genetics again and have only been working with Led for a year now. I have noticed that outdoor weed is simply stronger with a different buzz and hiccup than the same genetics grown indoors. The indoor plant wins in terms of appearance, which is of course also very important for the presentation of the product.
Pretty much my impression aswell; maybe not always stronger but a fuller, wider richer type of buzz, but rough looking buds with harder fibery texture for outdoors. Thx anyways :)
 

Ca++

Well-known member
I prefer to smoke the outdoor, and this is in England.
Many people won't even try it though. Weed snobbery is real, and how $100 8th's sell. Marketing outdoor is a lost battle here. Even giving it away.
If it's not obviously outdoor, and you can brand it off as a Sat that took months, it sells off it's own strengths. People don't need telling where it was grown. If they know, their programming kicks in, and they get more value from exercising their snobbery, than they could get paying for something that they think grows for free.
 
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