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How many grams per watt is a satisfying grow for you?

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  • Oct 15 2011 05:48 AM
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Posted 15 October 2011 - 05:48 AM

How many grams per watt do you guys consider to be a good successful grow? I'm curious
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Posted 16 October 2011 - 01:05 AM

It's a common misconception that yield efficiency can be accurately described in terms of weight per watt. The truth is that maximum yield increases at a faster rate than lamp wattage. This is because increases in light intensity can raise the size of a growing area in three dimensions. For example, a 400w can support maximum bud growth in roughly a 2.5' cubic area and yield up to about a pound. While it's exactly twice the wattage, the maximum bud growth area from an 800w isn't just two 2.5' cubic areas next to each other. It does double the width of the growing area, but also doubles the length & height as well, making roughly a 5' cubic area of maximum bud growth. The volume of this cubic space is actually eight times that of the 400w's area.

Now, because light is blocked by plant parts on its way down to the bottom of the maximum growth area, the vertical increase doesn't turn out to be twice that of the 400's in real life. You can, however, assume that the 800w can produce more than four times as much as the 400w. Growing the same sized plants, the 800 would yield a maximum of about 4lbs. Growing larger plants, the 800w lamp might produce an absolute maximum of about 6lbs.
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Posted 16 October 2011 - 02:34 AM

It's a common misconception that yield efficiency can be accurately described in terms of weight per watt. The truth is that maximum yield increases at a faster rate than lamp wattage. This is because increases in light intensity can raise the size of a growing area in three dimensions. For example, a 400w can support maximum bud growth in roughly a 2.5' cubic area and yield up to about a pound. While it's exactly twice the wattage, the maximum bud growth area from an 800w isn't just two 2.5' cubic areas next to each other. It does double the width of the growing area, but also doubles the length & height as well, making roughly a 5' cubic area of maximum bud growth. The volume of this cubic space is actually eight times that of the 400w's area.

Now, because light is blocked by plant parts on its way down to the bottom of the maximum growth area, the vertical increase doesn't turn out to be twice that of the 400's in real life. You can, however, assume that the 800w can produce more than four times as much as the 400w. Growing the same sized plants, the 800 would yield a maximum of about 4lbs. Growing larger plants, the 800w lamp might produce an absolute maximum of about 6lbs.


6lbs from 800W would be over 3g/W. thats absurd. the average yield from a 600 is about 3/4lb (a little over .5g/W). average on 1000 is about 1.5lb. again, close to .5g/W.

if you manage to pull over .5g/W, you should be happy. there are definitely ways to get better than that, but im personally satisfied with .5 or so.
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Posted 16 October 2011 - 03:24 AM

Since you're talking about grams per watt, you apparently missed the point.

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Posted 16 October 2011 - 12:10 PM

There are a couple different ways to measure efficiency. All are somewhat accurate, but differ greatly based on other factors.

What factors? And how?

Grams per watt: measure of efficiency based on power consumption. Important if your limited on power usage.

Grams per square foot or meter: important if your space is limited.

Grams per plant: important if neither of the previous two are limited, but plant count is.

Each of the above methods of measurement are different and specific to a method of growing.

If you pull a gram a watt, your doing good.(3 grams per watt is unheard of)

If you pull 700 grams out of a square meter, your doing good.

If you pull 24 OZ off a single plant indoors, your doing good.

It really all depends on where your "choke" point is, power, space or plants.

Each measure of efficiency is poor when applied to the wrong method. Apply the proper measure of efficiency to your grow and you'll see what I mean.

If you have unlimited space and power, and a plant limit, grams per watt is inefficient. Example:

If you are allowed 12 plants. Put those under 3 600 watt lights. You yield 1800 grams, 1 gram per watt. Great.

Now take all 12 plants and put each under their own 1000 watt light. If you only get a half gram a watt, that's 6000. Sure, you'd pay a much higher electric bill, but the yield more than covers it.

Which grower above did better? One got
a gram a watt(grower A). The other .5 per watt(grower B). If grower A paid a $200 electric bill, than grower B paid about $1000 in electric. Grower A has 1800 grams. Grower B has 6000. Both stayed within their plant limit.

Check your measure of efficiency vs your grow method. It matters.
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Posted 16 October 2011 - 08:26 PM

hey you idiots, i asked a simple question.... GRAMS PER WATT!!! my buddy who grows for the state has managed to get his yield up to 1.5 grams per watt using lattaces as his SCROG. i did not ask how light travels, how much area it covers, etc. i asked what you guys consider a satisfying grow. 3 grams per watt is unheard of!!! thats why i posted this, hearing my buddy was getting 1.5... i wanted some opinions? he also said 600 hps are the most efficient lighting.
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Posted 16 October 2011 - 08:27 PM

6lbs from 800W would be over 3g/W. thats absurd. the average yield from a 600 is about 3/4lb (a little over .5g/W). average on 1000 is about 1.5lb. again, close to .5g/W.

if you manage to pull over .5g/W, you should be happy. there are definitely ways to get better than that, but im personally satisfied with .5 or so.



thanks for answering the question! Apparently i didnt make myself clear enough.

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Posted 16 October 2011 - 08:28 PM

btw i'm satisfied with anything over .5 as well, but i always shoot for as close to 1 as possible.
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Posted 16 October 2011 - 09:49 PM

The real problem with grams per watt is that it does not factor in time. A plant grown 12/12 from seed that you harvest in 2 months cannot yield the same as a genetically-identical plant grown under the same light and same conditions but allowed to veg for 2 months and then 2 more months for flower.

But, even with problems in any kind of g/w analysis, general rule of thumb is 0.5 for your average grower, 1.0 as a target for good, experienced growers.

hey you idiots

That attitude is not going to get you much help around here. People put a lot of time and effort into answering you, they don't deserve the back of your hand...
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Posted 17 October 2011 - 12:14 AM

It's called frustration. You ask a simple question trying to start a nice thread and rather than getting answers; .5, .8, 1, 6?????? I get mr ebotony over here going off about other conditions?? Simple question... How many Gram per watt do you guys get? I'm already familiar with lighting and ideal growing conditions.
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Posted 17 October 2011 - 12:16 AM

Also, sorry for the aggression. I was just attacked myself for trying to help on another thread and now understand how that is considered a "back hand".

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Posted 17 October 2011 - 12:51 AM

hey you idiots, i asked a simple question.... GRAMS PER WATT!!! my buddy who grows for the state has managed to get his yield up to 1.5 grams per watt using lattaces as his SCROG. i did not ask how light travels, how much area it covers, etc. i asked what you guys consider a satisfying grow. 3 grams per watt is unheard of!!! thats why i posted this, hearing my buddy was getting 1.5... i wanted some opinions? he also said 600 hps are the most efficient lighting.


Sounds like your buddy has ALL THE ANSWERS ASK HIM!! If you think light is the only thing to factor in on your harvest weight is crazy!!! To many things happen in a grow that can effect the out come of your final crop. Ive never understood why ppl try to figure it out by lighting.
Like the others were telling you light displacement means alot. A single plant under a 400 will do the same as a single plant under a 600 if light is hung correct.
But to answer your question I would say a average was about .8 on my last grow with 1000 hps hortilux bulb.
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Posted 17 October 2011 - 12:58 AM

I'm not asking lighting questions!!! OR how to increase yield!!!! Im getting that down ony own. I'm simply asking what YOU GUYS consider a good grow?!!!? Simple right? No I'm getting paragraphs! My buddy gets 1.5 grams per watt consistently so of course I ask him tips! I'm getting close to 1 gram per watt and i dont need your guys novels? HOW ARE YOU GUYS DOING? Simple question

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Posted 17 October 2011 - 01:02 AM

Let me clarify myself, I am NOT asking lighting/yielding tips!!! I am asking what you guys get on average? Simple questions should consist of simple answers. I did not ask for your guys scientific explanations on a entire different subject!

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Posted 17 October 2011 - 02:42 AM

Also, sorry for the aggression. I was just attacked myself for trying to help on another thread and now understand how that is considered a "back hand".


Lol I saw that. Dude was a total douche but that's kinda weird how that shit lined up like that...
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Posted 17 October 2011 - 03:35 AM

I personally don't care about grams/watt. My goal is the highest quality bud I can produce. If I can produce beautiful, healthy, thriving plants that are covered in trichomes and swollen calyxes, then I will be very happy regardless of the yield.
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Posted 17 October 2011 - 03:54 AM

Well what if you've already mastered that aspect and you're just focused on maximizing yield now? That way I get maximum quality and yield for my environment. Again, people can't just answer a simple question. Bitter old timers.
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Posted 17 October 2011 - 03:57 AM

1/Gram per watt

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Posted 17 October 2011 - 04:12 AM

Well what if you've already mastered that aspect and you're just focused on maximizing yield now? That way I get maximum quality and yield for my environment. Again, people can't just answer a simple question. Bitter old timers.


I did answer it. If I gave you a gram/watt answer I would be lying to you because my definition of "success" is not related to yield. You asked what a successful grow is, and I answered.

Yield is also heavily strain dependent, which is another reason why it can't even be answered. For example if you are growing Blue Dream, I would want around .75g/watt, but if you are growing OG Kush, you should probably only expect .5g/watt. You see why just giving a number doesn't mean anything?

In general though I'd like to see .75g/watt out of my grows, but again, that doesn't mean if I got less that I'd consider it unsuccessful, not at all. Now I definitely concentrate on yield. For example I keep my light pressed as far as it can be pressed while not being TOO close and still spreading light over the canopy, and I train my plants to have a nice even canopy instead of growing tall trees, I grow in coco, feed every watering, etc., etc. All of that is to maximize yield. There is no reason not to try and maximize yield, but all I'm saying is that the final numbers don't represent if my grow was successful or not.
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Posted 17 October 2011 - 04:18 AM

OLDSCHOOLGROWER would know send him a private.


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