Most common and easy fix to massively increase yield. Plus dispell a myth

tip top toker

tip top toker

Well-Known Member
I use a 600w, i get a better yield with it closer. As simple as that.

You are trying to lump this idea in as rule of thumb in every grow.

The debate is whether putting a light closer is better than putting it farther in regards to yield.
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It's a little thing researchers would call controlling the variables. You are using a huge warehouse production system as your reference for bigger yields, i am using my personal grow. 1 situation proves that further away is better, one proves that closer is better. This means analysis and debate of these results is pointless, as you have not keyed in on the variables.

I'm not being argumentative, my plants give a bigger yield with them closer, or am i simply blind wrong in this regardless of ebing the grower?
 
skunky33

skunky33

Active Member
No a 150 watt you'd have to have colas inches away to stay in the optimum growth so that means if you're cola is 5 inches away it will only reach 6 more inches down in the center. any plant on the side more than 11 inches wouldn't get optimum growth it's minuscule. So, obviously it doesn't compare to 600 wts. I guess it would be good to determine strains into the mix, grow something like Critical with a month in veg, you want lights closer since a lot of quality growth grows on side branches. Some of my friends have skimpy grows and their lights are always very close, I listened to them and had pretty skimpy grows even though I had advice to lift up the lights a bit. I finally did and had much better results after I did a friend did and he yielded 25% more than usual with the same strain same set up. So there has to be something to it.
 
skunky33

skunky33

Active Member
TaoWolf said:
A majority of light is going to be blocked from lower foliage though - it would require a *significantly* higher amount of PAR hitting the top of the plant to maintain the minimum level of light required for full growth on leaves that are at the base of the plant. Optimally, even the lowest, most internal leaf would be receiving enough light to reach it's full production potential for the plant. One can't say any specific number of a certain measurement of light is adequate and that's all there is to it in the real world.

For example, there would be a huge difference between what would be required to adequately provide for a 4' tall bushy indica as opposed to a young 1' stretchy sativa. The needed PAR increases at an exponential rate with height/distance and according to how much foliage has to be penetrated. Unless you love a lot of popcorn bud, or only grow short, single-cola SoG plants, you'll have to go well above the minimum required PAR at the canopy to make all those other branches and leaves below the top layer get something adequate as well.

Otherwise, I'd ditch the 600w HPS and just use my 150w - I can cover the same 2'x4' area with enough light for minimal growth... but everyone knows (I hope) that a 600w is going to provide far more PAR to more of the plant and that equals more to harvest at the end of flowering...

With an air-cooled hood, my 600w is cooler at the same distance than my 150w as well. So I'm just not following the argument besides 'you could burn your plants if you get the light too close'...
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No a 150 watt you'd have to have colas inches away to stay in the optimum growth so that means if you're cola is 5 inches away it will only reach 6 more inches down in the center. any plant on the side more than 11 inches wouldn't get optimum growth it's minuscule. So, obviously it doesn't compare to 600 wts. I guess it would be good to determine strains into the mix, grow something like Critical with a month in veg, you want lights closer since a lot of quality growth grows on side branches. Some of my friends have skimpy grows and their lights are always very close, I listened to them and had pretty skimpy grows even though I had advice to lift up the lights a bit. I finally did and had much better results after I did a friend did and he yielded 25% more than usual with the same strain same set up. So there has to be something to it.​
 
TaoWolf

TaoWolf

Active Member
It sounds like we are pretty much in agreement to be honest... It's most likely the case that both you and your friend's plants benefited more from a lower temperatures/larger light footprints than the extra PAR gained from proximity and there's no real mystery/argument here?

Too close = temperatures will be too high and growth stunted.

Too far away = stretched plants with a poorly developed undergrowth and less possible production.

Sweet-spot = Optimal temperatures + optimal light footprint + maximum PAR.

Maybe people do put too much emphasis on proximity and not enough on temperature and light footprint in general and I just hadn't noticed it before. =P

What are the temperatures like at the canopy after raising your lights and what were they before?
 
J

Japanfreak

New Member
TaoWolf said:
Ah, all I get from that is to take the light footprint into account in addition to the heat... In any case it's saying ~18 inches for a 1Kw and ~12 inches for a 600w which sounds about average for an air-cooled hood in an enclosed space... It doesn't define what 'over-lighting' is or how that relates to PAR... Not trying to be rude, but I'm not seeing anything in that article that suggests anything different than what most people practice?
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I see people all over the net putting their lights 2 inches from their canopy. That's what I'm talking about.
 
G

GanjaneticallyBlessed

Member
I think the whole basis to this arguement is, that if the light is close enough to heat any part of the plant up to beyond optimal temperatures it's worse for the plant/yield.

It looks like some are having the misconception that they figure everything is fine because the tent temperature is optimal, and their hands placed under the light while ontop of the colas do not feel uncomfortably hot.

If you place your hand under the light and above the colas, 90-100 degrees is not going to feel uncomfortable. Yet while your plants sit in there 24/7, the top colas may actually be 90+ degrees even if your tent temperature is optimal. It makes perfect sense.

The solution seems to be either keep the lights far enough from the canopy so that they are not physically heating to colas beyond optimal temperatures, or just place a fan in the grow room to cool the upper most sections of the plants.

I have yet to do a grow myself but this information seems like blatantly obvious common sense. I'm definately going to add a wall fan into my tent after this read. Thanks for the advice.
 
skunky33

skunky33

Active Member
Old post. What I'm talking about is optimum cola temperature. Even if a light passes "the hot hand" test, it's still may be to warm for optimum results especially without supplemental Co2. I find there is a delicate balance to get optimum results of light distance and cola temps.
 
blacksun

blacksun

New Member
Yeah...I can keep my kolas at 75 degrees no matter how far away my light is, all year long (ah the joys of having ac for both the tent and the lighting system, a heater for the winter, and proper circulation and ventilation).

However, I run a high quality bulb and high quality ballast (600w hps). Combined, I cannot get closer than 18" to plant tops without getting light bleaching (with a brand new bulb...of course they lose power with use).

Most light charts you find plastered online will specify that you can get all the way to 9" or even 6" from the plant tops with a 600w. I guess they must be referring to old or low quality bulbs+ballasts.



Anyways, I mention this because it kind of does tie into your "move the lights away to get better yields" theory, but for a completely different reason than you were shooting for.
 
Q

QuackQuack

Member
I don't see how anyone can argue that a 1000HPS should be within 6" of a plant. Try it. Your plant will be fried within a couple of hours. Just hold your hand under it for a couple minutes (if you can). Yeah, there's more lumens, and more photons, but your plant can't utilize them when it's dying from the excess heat.
 
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