Please explain the phrase "Penetration" in reference to lights.

[POTUS]

I keep running into the phrase "Penetration" in reference to the use of lights on an indoor grow. Statements like "Provides better penetration" and "Not enough penetration".

Scenario: A grow room that is covered wall to wall with plants. The leaf canopy of plants is in excellent health and has no openings in it as viewed from the top.

I'd like to hear everyone's take on exactly what this means to them if applied to the above scenario.

1. What is "Penetration"?

2. Why is penetration needed?

3. What happens if penetration is not present?

Please answer these questions specifically in reference to the scenario as stated above.

To be fair, I have to make it clear that I believe "Penetration" to be another fallacy in the minds of over-enthusiastic growers that have picked up a trade phrase that is inappropriately used and has no real merit.

Anyone who can provide me with ANY professional reference to Light Penetration that specifically means beneficial light reaching through a plants leaf canopy to the lower leaves of the same plant and providing something NOT gained by the upper leaf canopy, please do so. I'm betting that no one can. Please don't swamp me with anecdotal stories.

I would be especially interested in any comments on the benefit of actually *removing* leaves to allow "penetration" to the lower areas of the same plant.

Please keep in mind that I am NOT trying to start an argument. I'm trying to bring a misconception to light and explain to everyone how this fiction of "Light Penetration" is a well spread myth that holds no true scientific basis or benefit.

In actuality, I would love it if someone proved me wrong with quotes from anyone who is a plant biologist or other professional in the field. Please link to any articles or studies that show me being incorrect.

Thanks,

Stoney

 

[Puffin Afatty]

:farm: When I refer to light penetration, I mean the distance the light remains effective during flowering

With a 400w hps lamp, the effective radius is 22 inches from the lamp in all directions, 33 inches with a 600w and 53 inches with a 1000w etc. it's an energy thing.

any buds beyond the radius will not get enough light

as far as the canopy coverage, in my experience, I see that it does help to get light to any part you want to grow, within the effective radius however, I dont believe in removing leaves to accomplish this, I prefer a lst, scrog or other bending style :hubba:

 

[The New Girl]

I'd like to hear everyone's take on exactly what this means to them if applied to the above scenario.

1. What is "Penetration"?

2. Why is penetration needed?

3. What happens if penetration is not present?


Stoney

1. I think I know
2. For satisfaction usually
3. Definitely no babies.

Hi POTUS -
I hear that and think the light isn't getting through to the lower buds/leaves cause it's being blocked by the upper ones, probably wrong on my thinking but that's what i get, not penetrating to the bottom because it's blocked...(i don't mean going through the leaf like x-rays)

 

[POTUS]

1. I think I know
2. For satisfaction usually
3. Definitely no babies.

Hi POTUS -
I hear that and think the light isn't getting through to the lower buds/leaves cause it's being blocked by the upper ones, probably wrong on my thinking but that's what i get, not penetrating to the bottom because it's blocked...(i don't mean going through the leaf like x-rays)

Ref: 2. For satisfaction usually
Call me: 1-555-444-1212 HAHAHAAHA

The light that contacts any leaves on the plant benefits the entire plant, not just the part that the light hits. Having it hit somewhere else on the plant is pointless. The plant will create additional leaves to gather sunlight until it's maxed out or as close as possible. Removing leaves to let sunlight through to other leaves is crazy.

 

[POTUS]

:farm: When I refer to light penetration, I mean the distance the light remains effective during flowering

With a 400w hps lamp, the effective radius is 22 inches from the lamp in all directions, 33 inches with a 600w and 53 inches with a 1000w

any buds beyond the radius will not get enough light :hubba:

Interesting way of looking at light distance. In your case, what would the word "penetration" mean? What is the light penetrating? I think a more accurate method of expressing your view of this would be to say "The effective distance of the light". Since the light isn't penetrating anything but air. It's confusing to the newbies to use the word "penetration". It makes them think that the light needs to actually hit the lower parts of the plant, which isn't true. The lower parts of the plant gain from the total light striking the plant. The upper portions of the plant have more buds because the plant is genetically dispositioned to form buds nearest the top of the plant for protection of the seeds from seed eating predators. The lower part of the plant is barren mostly for the same exact reason.

 

[Puffin Afatty]

Interesting way of looking at light distance. In your case, what would the word "penetration" mean? What is the light penetrating? I think a more accurate method of expressing your view of this would be to say "The effective distance of the light". Since the light isn't penetrating anything but air. It's confusing to the newbies to use the word "penetration". It makes them think that the light needs to actually hit the lower parts of the plant, which isn't true. The lower parts of the plant gain from the total light striking the plant. The upper portions of the plant have more buds because the plant is genetically dispositioned to form buds nearest the top of the plant for protection of the seeds from seed eating predators. The lower part of the plant is barren mostly for the same exact reason.

Yes, my use of penetration is gramatically clumsy, when effective radius does a better job of conveying the message.

Semantics aside, the lower part of my plants are anything but barren, as I use the lower portions to regenerate. If you keep the lower portion of the plant within the effective radius, it will grow buds just like the top, again, it's an energy thing.

Outdoors you dont have this issue as the sunlight has adequate energy where ever it happens to strike the plant.

your issue seems to be with folks claiming it necessary to remove leaves to allow lower areas within the effective range, to get some light from above.
I have to agree, it seems counter productive to remove anything contributing to the growth of the plant, when you can simply bend the plant to allow the light to reach everything within it's effective range

 

[POTUS]

Yes, my use of penetration is grammatically clumsy, when effective radius does a better job of conveying the message. Semantics aside, the lower part of my plants are anything but barren, as I use the lower portions to regenerate. If you keep the lower portion of the plant within the effective radius, it will grow buds just like the top, again, it's an energy thing. Outdoors you don't have this issue as the sunlight has adequate energy where ever it happens to strike the plant. your issue seems to be with folks claiming it necessary to remove leaves to allow lower areas within the effective range, to get some light from above. I have to agree, it seems counter productive to remove anything contributing to the growth of the plant, when you can simply bend the plant to allow the light to reach everything within it's effective range.

My issue is really with the phrase itself. When someone says that a certain light has "better penetration", it's makes me cringe. The phrase is meaningless. You can just as well say: "This will increase the speed of photon impact on the epidermis of the leaf to facilitate the rapid transference of energy to the receptors of the plant". It SOUNDS like it means a lot, but in actuality, it's pretty much self pumping baloney.

BTW, I disagree with you on the lower parts of the bush producing equally with the top. After growing many thousands of plants, I have yet to see one that did so. If you cut the top off, then the bottom becomes the new top, hehe. Please show me a bush that has an equal amount and size of buds that the top of the same plant does.

Not trying to argue with you man. Just trying to sort the facts for the newbies that are on their first grows. Too many misconceptions are being propagated.

 

[slowmo77]

so does it matter if light hits the lower buds or not?
does the light hitting the top leafs feed the lower leaves as well?
will the buds stay the same size on lower parts of the plant if they get direct light or indirect light?

 

[trillions of atoms]

i agree, the use of the word penetration is a bumbled one....i to -prefer bending and tucking.

cutting only to take clones or fim.


I think they look at crowding and try and explain the lower buds not getting light with the word penetration.

All this talk of penetration makes me wanna call that 555 number :rofl:

 

[POTUS]

1. so does it matter if light hits the lower buds or not?
2. does the light hitting the top leafs feed the lower leaves as well?
3. will the buds stay the same size on lower parts of the plant if they get direct light or indirect light?

1. No. You'll gain no over-all weight by lighting the lower branches. The light will be much more effective if directed at the upper branches. The plant sends a growth hormone to the upper branches that MAKES the top of the plant produce more. This hormone is almost absent in the lower branches.

2. To some extent, yes. However, the top of the plant is where nature will concentrate the growth hormones and resulting buds.

3. No. They will not. I'd love to see some pics of anyone who can produce a plant that does that. The weight of bud on the top branches will far outweigh that of the lower branches regardless of lighting on the lower branches.

 

[POTUS]

All this talk of penetration makes me wanna call that 555 number :rofl:

You're a dude aren't you? hehe, don't be calling me man. I don't swing that way....hahaahahhaa

 

[trillions of atoms]

LOL i thought Smokinmom or sport was answering that line

 

[slowmo77]

this is a good thread. learn something new every day.

so what your saying is its better have alot of light above then a little all around.. its gonna process light the same way no matter whether it comes from the top or the sides.

is that right?

 

[Puffin Afatty]

My issue is really with the phrase itself. When someone says that a certain light has "better penetration", it's makes me cringe. The phrase is meaningless. You can just as well say: "This will increase the speed of photon impact on the epidermis of the leaf to facilitate the rapid transference of energy to the receptors of the plant". It SOUNDS like it means a lot, but in actuality, it's pretty much self pumping baloney.

BTW, I disagree with you on the lower parts of the bush producing equally with the top. After growing many thousands of plants, I have yet to see one that did so. If you cut the top off, then the bottom becomes the new top, hehe. Please show me a bush that has an equal amount and size of buds that the top of the same plant does.

Not trying to argue with you man. Just trying to sort the facts for the newbies that are on their first grows. Too many misconceptions are being propagated.

again with semantics, ok, I'm not an english grammar teacher

:farm: your gereralizations aside again, my point about the lower branches producing if given the light, is illustrated in my little thread on the regeneration of my current stash plant, SnowWhite, the bottom branches made the largest colas. Hard to tell, but the bottom is the left side, since She is horizontally inclined, again, so to speak:hubba:

 

[Aurora_Indicas_Dad]

you probably read a post of mine.i like the sounds of "the light puts out 95,000 lumens of light which is sufficient to penetrate 3 1/2 feet into the canopy of the plants" its alot easier for a noob reading it.i think your just a lil shy when it comes to the word penetration. not only is it how we are all put on this earth,but its also used when talking about lighting.my directions for hydroponic systems used the word as well.we are all young and old adults in here and should beable to hear the word penetrate without thinking of intercourse =) i mean come on,dont we all like havin sex? last i checked we all have hormones.if your old and cant perform anymore,no need to get shy when ya hear the word...i dont whayelse to say,but thats my $.02 about this topic

 

[lyfr]

i aint to smart so i apologize for jumpin on the "penetration" bandwagon. i will no longer be using this term as not to confuse people wrong/sloppy term. i have a 400 and i would never say buds at bottom are as big as buds on top, i dont care if you flower from seed and they only get 10" tall, they wont and they haven't. but in my measley 4 and3/4 grows, I have noticed that the canopy's (top of plants for newbs ) that have gotton taller than 24" have had very airy buds with little trich's on the bottom. the one's that stayed around 18" have had much denser buds with many more trichs. i just happen to have some now that are 18" and 4 1/2 wks flower and i get a pic of a bud on the very bottom of plant at lights on to show this...i will include a pic of the tallest closest-to-light bud for comparison. my point is simply that the bottom buds will be extremely better if plants are kept shorter when using smaller lights...never meant to portray that they would be = to top buds...but i ain't so smart.
and i never cut anything of my plants ever...and wouldn't suggest doing it at all in flower.
just to make sure i learn something, are you saying no matter how big your plant gets with any light the bottom buds will remain exactly the same...as in with a 400hps, bottom buds will be the same whether plant is 12" tall or 48" tall? Not trying to start an arguement just want to understand so i wont be misinforming people, as i like to help.
great discussion BTW !

 

[slowmo77]

im gonna say that i hope no newbies read this thread.. you guys have confussed the heck out of me.. some ones signature says if you can't explain it simply, you simply don't understand it.. i think thats what we have here.

is this how it works..
this is just for education not a fact

400000 lumens from above = 2 oz of bud
400000 lumens from the side = 2 oz 0f bud

is that what your saying? the light no matter where the plant recieves it produces the same amount of bud? due to the plants hormones it sends the big buds to the top and lower buds will remain the same no matter what? i really am confused at this point.

 

[slowmo77]

i wouldn't call this an argument at all. as far as i know know one is angry or i hope they're not. this is all confussing

 

[lyfr]

as long as were getting the "terms" straight..."penetration" is a WORD...not a "phrase" ! im done here...this thread is for nothing but creating conflict by nitpickin word usage....IMAO, of course

 

[Aurora_Indicas_Dad]

lol,i agree.it doesnt matter how we explain stuff.i understand the word and terminology of the word completly and see no need to ask why someone used it in a thread.now please close the thread =)