Old school/New school observations and questions

I'm still new to this, I'm not trying to start an argument (and hopefully people can keep this civil), I'm just relating my experience and trying to understand the fundamentals about how plants use different kinds of light, and what is the measure of a truly healthy plant.

One of my first LEDs was a cheap Chinese light (170+/- real watts), in the "it was cool at the time" red/blue configuration. I had a plant under that for several weeks, and it was growing very slowly, had very dark leaves, and the space between nodes was next to nothing, it was very dense.

I then "upgraded" to an Optic Vero COB (120W), and within a day or two the plant changed (still on 18/6). It began to grow upward very quickly, the new growth was pale green, and the space between nodes got much larger. So a plant that was not getting much taller but was getting thicker and denser, is acting as though I switched to 12/12 and is opening up and stretching (but I haven't switched the timing at all).

My initial response was to think that the Optic was under-powered, and the plant was stretching because it was not getting enough light. But based on all the threads here on "quality of light", that seems unlikely. As a side note, the distance between the plant and the lights has been consistent (around 12").

Any idea why the red/blue would have the growth pattern it provided, and the Optic produced such different results? Was the plant "happier" or healthier under just the old light, i.e. getting more of what it needed?

Oddly, I had similar growth patterns with my very first LED experiment, a Home Depot shop light (149w 4000k). It gave me very dense, dark, short thick plants when I vegged under it. Very slow growth, but heavy foliage. If the space between nodes were the primary measure of healthy plants, then at this point the HD shop light is outperforming the COB... (at least in veg).

Which is why I'm asking, what is the measure of a healthy plant?

What color temp is the optic?
If your plant is sativa dominant it is stretching more under the 3000k than the 4000k shoplight or the blurple because it is receiving less blue now.

It also will look more pale under the warm white.

Not necessarily a "health" thing. If you are not satisfied with the way your plant is shaping up, add blue or grow a more indica dominant strain.

Bon chance grower!

The optics come in 4000k I believe.

I vegged some plants under 3000k/4000k where they stayed squat and when I put them under the sun, they stretched.

IMO, genetics and the swapping of lights would be the biggest factors, without being able to explain why. The leaf color changing could be due to stress from the swap but there are a lot of variables to consider.

nogod_ said:

What color temp is the optic?
If your plant is sativa dominant it is stretching more under the 3000k than the 4000k shoplight or the blurple because it is receiving less blue now.

It also will look more pale under the warm white.

Not necessarily a "health" thing. If you are not satisfied with the way your plant is shaping up, add blue or grow a more indica dominant strain.

Bon chance grower!

Click to expand...

Hilo is right, the Optic is 4000k. My patient prefers Sativa dominant, but I'm not sure if you're saying that Sativas prefer a different color temp than Indicas? Or are you just referring to Sativas tendency to stretch in general?

I just put both lights (the old and the new) in side by side for now. Just did that yesterday, so I can't say if it will have any effect. I figure when in doubt, use them all, and there was enough room and enough of a window in the room temp, so I went for it. If it continues stretching at the rate it has been for the past few days, I'll probably have to flip it to 12/12 within a week so I don't run out of vertical height in the grow space.

HiloReign said:

The optics come in 4000k I believe.

I vegged some plants under 3000k/4000k where they stayed squat and when I put them under the sun, they stretched.

IMO, genetics and the swapping of lights would be the biggest factors, without being able to explain why. The leaf color changing could be due to stress from the swap but there are a lot of variables to consider.

Click to expand...

I had something very similar happen with putting short dense plants outside and having them totally open up and shoot vertically, and it made me wonder if the Optic is closer to sunlight, since it seemed to initiate a similar response.

Which also made me wonder if a certain amount of stretching (or distance between nodes) isn't the "normal" healthy shape of these plants, and perhaps the heavy infusion of either red/blue or some other form of partial light spectrum or temp, might not induce a sort of mutation of short node space... sort of artificially stunting their growth.

I've not yet tried to go all the way through flower with either of the lights that produced the dense plants, maybe after this series I'll try it.

I dont think the strain has any preference. Its more about your height requirements. If you want stockier plants add more blue or grow more indica dominant strains. If youve got adequate penetration or supplemental light and no height restriction leave the optic as is and let 'er rip.

The "health" has more to do with the plants' diet than the light spectrum. There are a few documented grows on here using the optic. Do they all look unhealthy?

Humanrob said:

Hilo is right, the Optic is 4000k. My patient prefers Sativa dominant, but I'm not sure if you're saying that Sativas prefer a different color temp than Indicas? Or are you just referring to Sativas tendency to stretch in general?

I just put both lights (the old and the new) in side by side for now. Just did that yesterday, so I can't say if it will have any effect. I figure when in doubt, use them all, and there was enough room and enough of a window in the room temp, so I went for it. If it continues stretching at the rate it has been for the past few days, I'll probably have to flip it to 12/12 within a week so I don't run out of vertical height in the grow space.



I had something very similar happen with putting short dense plants outside and having them totally open up and shoot vertically, and it made me wonder if the Optic is closer to sunlight, since it seemed to initiate a similar response.

Which also made me wonder if a certain amount of stretching (or distance between nodes) isn't the "normal" healthy shape of these plants, and perhaps the heavy infusion of either red/blue or some other form of partial light spectrum or temp, might not induce a sort of mutation of short node space... sort of artificially stunting their growth.

I've not yet tried to go all the way through flower with either of the lights that produced the dense plants, maybe after this series I'll try it.

Click to expand...

nogod_ said:

I dont think the strain has any preference. Its more about your height requirements. If you want stockier plants add more blue or grow more indica dominant strains. If youve got adequate penetration or supplemental light and no height restriction leave the optic as is and let 'er rip.

The "health" has more to do with the plants' diet than the light spectrum. There are a few documented grows on here using the optic. Do they all look unhealthy?

Click to expand...

I'm not trying to knock the Optic lighting, didn't mean to come across that way (although I do question whether another $150 and a move to the 200w would not have been a better choice). I'm actually wondering if the Optic isn't producing a more natural and therefore healthier version of the plant. I definitely have seen that Optic lights can do an awesome job -- that's why I bought one!

Here are some quick pics of the space in its current form... In the last one you can see the shape of the new growth being different than the bottom part of the plant.


As a side note, would anyone suggest that I turn the plant from time to time? Does it matter that one half is getting one kind of light, and the other half is getting a different kind???

Assuming all factors stayed the same and all that changed was the lighting, "diet" shouldn't be of concern. I'm operating under the impression that he knows how to grow this plant.

The plant looks fine IMHO and this is pure speculation but I believe when plants stay squat it's because of an excess of blueish wavelengths without all the in between "supplemental" wavelengths. In your case, with the introduction of said wavelengths (and more) the plant is showing its true expression.

As for moving/rotating your plant, I've asked myself the same question. On one hand, in a natural setting they'll never rotate or move... On the other, it may be beneficial for "even" development. Kind of like how pruning can improve yield in some cases.

Humanrob- That Home Depot light you have is only 75 lumen per watt. Lowe's has a 40 watt light that is 105 lumen per watt for $50. This has been one of the cheapest 4' replacement I have found so far.

nevergoodenuf said:

Humanrob- That Home Depot light you have is only 75 lumen per watt. Lowe's has a 40 watt light that is 105 lumen per watt for $50. This has been one of the cheapest 4' replacement I have found so far.

Click to expand...

Thanks for the heads up. I'm not in the market for another light right now, and as it turns out, both of my indoor spaces are under 48", so I can't fit 4' lights in either of them. That was part of what appealed to me about the one I got, its something like 22"x16". It currently lives in a metal rack that I use for vegging young ones. I'm not into paying more for something just because it comes in a fancy wrapper, but that said if there is scientific evidence that the light coming from a designated grow light is superior for growing, then that's what I would get. I'll use whatever works, and this one still serves a purpose.