# Yield per Watt



## Landing (Oct 13, 2014)

Since I'm tight on space, I'd like to ask - what affects yield per watt?

As far as I can tell, there is the strain, the height of the bulb, the temperature, plant size, etc.

But I think the only two things I don't have a good grip on are nutrients and air flow.

How much do plants need oxygen/Co2?

And which nutrients are best for soil? 

I've seen people get 1.5g/w and 100g out of a 30x30cm plant. I got the same result with a plant 4x as large (60x60cm).

Thanks for the help!


----------



## The Hemp Goddess (Oct 13, 2014)

Have you seen that on You Tube or with your eyes?  Even if it is someone you know, there is a good chance that they are "fudging" on their yield numbers.  There are a whole lot of people who will lie about yield.  I do question a 100G yield with a 150W light...and a 4 ox plant in a space smaller than 1 sq ft.  A yield of 1.5 grams per watt is a large yield.  I would guess that not 1 in a thousand get that kind of yield.  New growers need to quit focusing on yield and focus on getting your grow space dialed in as best you can.  

More light will increase yield, up to a point.  At some point, more light does no good.  However it also is determined by the type of bulb.  CFLs will not produce as much bud as an HPS.  The kelvins are also important.  You want blue light for vegging and red light for flowering.

Adequate ventilation--Good ventilation is critical--it is almost as important as your lighting.  Plants need a continual supply of fresh air all the time the lights are on for proper photosynthesis.  I like to exchange the air in my space 2-3 times a minute.    

Temps, keep the temps in the 60-80 range with around 70 being ideal

RH--keep within parameters.

The plant size is kind of immaterial.  If you had a plant that was 4 x as large but using the same light, you got the same yield per watt.  It is yield per watt, there is no way to calculate plant size into that.

Nutrient choice is a real individual thing.  I personally like General Hydroponics products.  I use the Flora products for hydro and the General Organics line for soil.  You want a vegging nutrient that is high in N and K and lower in P.  For flowering, thye need very little N (too much N inhibits flowering) and more P.


----------



## Landing (Oct 13, 2014)

The Hemp Goddess said:


> The plant size is kind of immaterial.  If you had a plant that was 4 x as large but using the same light, you got the same yield per watt.  It is yield per watt, there is no way to calculate plant size into that.
> 
> Nutrient choice is a real individual thing.  I personally like General Hydroponics products.  I use the Flora products for hydro and the General Organics line for soil.  You want a vegging nutrient that is high in N and K and lower in P.  For flowering, thye need very little N (too much N inhibits flowering) and more P.



I actually saw it on this forum.. just don't recall where.

It was a 600w 1mx1m and he had 9 plants which I'm estimating must have been 30x30cm because they were bunched up closely, and he said he got 100g from each plant which is like 1.6g per watt

If what you're saying is true, then why did I only get 500g out of a 1000w bulb? I should have gotten 200g per plant instead of 100g.

I mean, if a 30x30cm plant can grow 100g, then my 60x60cm should have grown 400g and I should only have to grow two under the 1000w..

So, if that's true, why didn't it happen?


----------



## P Jammers (Oct 13, 2014)

Landing said:


> I actually saw it on this forum.. just don't recall where.
> 
> It was a 600w 1mx1m and he had 9 plants which I'm estimating must have been 30x30cm because they were bunched up closely, and he said he got 100g from each plant which is like 1.6g per watt
> 
> ...




There are lots of variables. Strain type, veg times, proper training for maximum light exposure, air exchange, proper feeding, bulbs, etc.etc. 

I've seen many who grow their entire life and never achieve the 1GPW numbers, while others can achieve that easily. 

There is no real single factor that will make a person achieve those numbers, and certainly not the first time out on a plant from seed. 

Practice is key and working a specific pheno 3, 4 or five times for many is what it's gong to take in order to know what can, and can not be achieved. It's certainly not something that is going to happen until you fully understand said pheno, work it a few times with different foods, training methods including veg times. 

I'd also agree with THG that many just throw these numbers out making claims of this or that with no visual evidence, and I see plants all the time that look like they will be barley a zip, and the grower is claiming 3 to 4 zips. I really love it when they finish a grow, and 2 days later they are giving weight numbers, and claim "dry weight". 

I'd love to see the thread if you can find it, but those numbers for me don't jive keeping it real.


----------



## orangesunshine (Oct 13, 2014)

search some NC posts---bet he's banged out 1.5 per watt on a regular basis


----------



## zem (Oct 13, 2014)

yeah I remember that fantastic 600w grow on another forum, the guy built coliseum style vertical grows, SOG perfected like never seen, he claimed to have harvested 2.1G/W! I was so intrigued to do a similar design grow, it made sense to me that building such a vertical setup, will increase yield significantly, just never gave it the time to build


----------



## The Hemp Goddess (Oct 14, 2014)

I agree, you have to learn to walk before you run.  Most new growers are too focused on yield when they should be focused on getting their grow space dialed in.  With temps like you have, you are never going to be able to achieve those numbers.  GET YOUR GROW SPACE DIALED IN AND THE YIELD WILL COME.


----------



## Landing (Oct 15, 2014)

P Jammers said:


> There are lots of variables. Strain type, veg times, proper training for maximum light exposure, air exchange, proper feeding, bulbs, etc.etc.



Well, isn't there some kind of guide for maximizing yield?

As far as I know, I have almost everything right.



P Jammers said:


> I'd love to see the thread if you can find it, but those numbers for me don't jive keeping it real.



Multi found it:



multifarious said:


> here
> 
> 33oz cured (924g)
> 600w
> ...



Yes, that's the one.

I have two questions:

1.) How did you get a 30x30cm plant to yield as much as a 60x60cm plant? If plants size is directly comparable to yield outdoors then indoors yield should be directly comparable to the amount of light. If I have 1000w and two large plants, they should both yield 500g, while smaller plants would yield say 250g each, no? So, what is keeping plants from reaching that 1g/w?

2.) You say "900g cured". Is the cured weight higher than the dried weight? If you simply dried the buds outside for two weeks, what would the yield be then?



multifarious said:


> Get your temps in line 1st and buy an ec meter so you can test the ec of your municiple water and your mixed nutrients.



Would an EC Meter be able to accurately gauge the amount of nutrients I need or would it just convert ml to ppm? If so, why is it necessary?




multifarious said:


> My belief is that you are trying to run before you have learnt to walk.



A better analogy, in my mind, would be that I am walking slow amidst a herd of joggers and attempting to ask each one as they pass me how they do it.

I did the same thing in regards to computers and hardware. I asked enough questions that I became the jogger, then the runner.



multifarious said:


> You "will not" achieve great gpw until your grow space is fully dialled in and you have gained a lot more experience.



Can you give me a checklist of items I need to check to know if my grow room is properly dialed in? Like lights/sq. meter, temps, etc.?

I think I'm like 70% dialed in but I'm not sure.




multifarious said:


> I tend to run x4 indoor harvests per year, typically in my circumstances, the winter/early spring and fall/winter harvests are better than the late spring and summer harvests due to the outdoors ambient temperatures as I do not use AC



Yes, I have found the same to be true for me, living in a pretty hot climate (32C average for most of the day in the summer)

If I do indeed get better results in the fall/winter then it would be proof that my temps are simply too high.



multifarious said:


> IMO your 1000w lamp and ventilation system just aren't working in your favor. You have constantly been experiencing high temps during your last 3 grows. The easiest and quickest solution to your woes would be to lower your temps. I believe that the easiest and cheapest  way for you to achieve this would be to use a 600w instead of your 1000w rather than upgrading your extraction system.



But then I'd have 600w in my 4m2 area. That's less than half the minimum recommended.

Also, I was under the impression that you shouldn't exceed removing all the air in your grow area in 2 minutes because anything faster wouldn't allow the plants to draw in the oxygen and C02 from the air.

This is why I chose an AC, as it seems the only option viable for having a lot of light with high ambient temps.

P.S. What is that photo of in your sig and did you take it yourself?


----------



## P Jammers (Oct 15, 2014)

multifarious said:


> here
> 
> 33oz cured (924g)
> 600w
> ...


I am curious is this the 33 oz in this pic?


----------



## Landing (Oct 15, 2014)

P Jammers said:


> I am curious is this the 33 oz in this pic?



Yeah, it's the same pics he posted last time.

I am just curious if curing had something to do with the weight.


----------



## P Jammers (Oct 15, 2014)

Landing said:


> Yeah, it's the same pics he posted last time.
> 
> I am just curious if curing had something to do with the weight.


Only if it was cured with lead.

Dry/cured = same thing in terms of weight.


----------



## bwanabud (Oct 15, 2014)

P Jammers said:


> Only if it was cured with lead.



:rofl:


----------



## goats_head_soup (Oct 15, 2014)

topping and lst'ing added about 50% increase in yield for me. Of course SOG is different but here we have number counts. But not topping and growing 4ft Christmas trees with just one cola was an earlier grower mistake I made long ago


----------



## Landing (Oct 16, 2014)

multifarious said:


> Why yes, yes it is pj



Oh, come on, man. Why is it that every time I ask you a bunch of questions you answer exactly none of them? It's really frustrating that I have to piece the information together that is obvious to you..



multifarious said:


> X9 Kaliman Cheese (TimeforPlanB cuts)
> 11ltr pots
> Cellmax Rockwool medium
> Recirculating drip, 150ltr Rez
> Lucas



Ah, I see. So it was in Hydro. That certainly helps explain it.

And you're using Lucas which is basically GHE Flora, which is terrible for soil.

Bah.



multifarious said:


> My Bubble hash
> My picture



Oh, I thought it was a seed.

That's neat. How did you take that shot?


----------



## Landing (Oct 16, 2014)

P Jammers said:


> Only if it was cured with lead.
> 
> Dry/cured = same thing in terms of weight.



Are you sure?

Then how come after two days of curing the buds FEEL more moist?

I also weighed the buds before (156g) and after (170g).


----------



## AluminumMonster (Oct 16, 2014)

It is physically impossible for the buds to weigh more after being chopped. Unless you are adding something to them.

The buds feel moist again because the moisture that was in the center of the bud distributes itself evenly throughout the bud when you store it in a sealed container.


----------



## Landing (Oct 16, 2014)

AluminumMonster said:


> It is physically impossible for the buds to weigh more after being chopped. Unless you are adding something to them.
> 
> The buds feel moist again because the moisture that was in the center of the bud distributes itself evenly throughout the bud when you store it in a sealed container.



But that's impossible.

I dried some buds to the maximum. They were totally dry.

I put them in a mason jar and two days later.. they felt moist.

My theory is that they soaked in the moisture in the air.

What else could it be?


----------



## P Jammers (Oct 16, 2014)

Landing said:


> But that's impossible.
> 
> I dried some buds to the maximum. They were totally dry.
> 
> ...



What he said above is correct.


----------



## Landing (Oct 16, 2014)

P Jammers said:


> What he said above is correct.



Who? Me or the other guy?


----------



## Locked (Oct 16, 2014)

Landing said:


> Who? Me or the other guy?



PJ is talking about AM.  Either the center of the buds still held some moisture that was drawn out or you jarred them with some super moist air.   Plenty of times when I jar my buds after a hang dry they become moist again.  That seems to be the norm. At least for me.


----------



## The Hemp Goddess (Oct 17, 2014)

GH is good with soil, you just have to use all 3 parts.  Many many people here use the General Hydroponics 3 part Flora series with soil and have great harvests.  

GHE and GH Flora are the same line of nutrients.


----------



## goats_head_soup (Oct 17, 2014)

Landing said:


> But that's impossible.
> 
> I dried some buds to the maximum. They were totally dry.
> 
> ...



It can take 2weeks or more sometimes to fully dry. Many times you think its dry but like mentioned b4 the moisture in the center redistrubes evenly when in a sealed container.make sure thick stems fully snap b4 jarring


----------



## orangesunshine (Oct 18, 2014)

Landing said:


> But that's impossible.
> 
> I dried some buds to the maximum. They were totally dry.
> 
> ...



they were NOT totally dry when you jarred them---don't believe it---get a super inexpensive strip to measure the moisture in the jar---it will tell u the same thing

AM is 100% correct---ur herb did not gain weight when you jarred it---moisture in the flowers was only redistributed evenly thru the bud---what u were calling dry was just the outside of the flowers and moved to the outside from the center while in the jar---this is the primary reason you need to BURP your jars during the cure


----------



## Landing (Oct 19, 2014)

The Hemp Goddess said:


> Many many people here use the General Hydroponics 3 part Flora series with soil *and have great harvests*.



So, you're saying it's possible to use GHE Flora on soil and get good results? How?

I used it and my yield went from ~105g per plant to ~75g per plant.

Should I just use more of it?



orangesunshine said:


> they were NOT totally dry when you jarred them---don't believe it---get a super inexpensive strip to measure the moisture in the jar---it will tell u the same thing



Mhm.

Well, I suppose it is possible. I dried them under a fan for 4 days, which is twice as long as it takes for them to FEEL bone dry.

I guess I can try drying them for a week next time and redo my tests. I'll post results here.


----------



## darklotus760 (Oct 19, 2014)

Hi Landing,
I have learned from myself being a new grower that you can't always rush cannabis especially when drying you may think it is dry but it is not a extra few days or weeks plus burping your jars well they cure helps a lot. As for the GHE Flora hemp goddess knows what shes talking about as well as Hammy they have a lot of good knowledge. I myself will be using GHE Flora on a soil/soilless soil. I say soil/soilless because I am going to be using Pro mix with worm castings and kelp and other organic nutes but most organic grows say it is not organic because it is not soil but that there own opinion. And as for a big yield it is trial and error most on here got quite a few grows under there belt as well as have grown the same strain so many times that they can make there plants yield to its full potential. I just hope that one day I can do the same once I get past the trial and error process and find a strain that I can nurture and learn to make it yield to it's full potential like these other pot genies. lol


----------



## The Hemp Goddess (Oct 20, 2014)

Landing said:


> So, you're saying it's possible to use GHE Flora on soil and get good results? How?
> 
> I used it and my yield went from ~105g per plant to ~75g per plant.
> 
> ...



 Yes, that is what I am saying.  Hammy doesn't run hydro and he does great with the GH products.  You need all 3 parts and you have to mix it in the proportions given on the bottle.  The proportions are different for differing growing phases.  If you did not use all 3 parts in the correct proportions, that is a reason for decreased yield.  As to whether to use more....how much of each did you use during veg and flowering?  

 There can be so much variance in different plants that trying to gauge yield by comparing different plants is a useless endeavor.  Even plants from the same mother can and do produce differently.  No matter how much you may believe that you treat your plants equally, there is always some variation in how they grow.  

 I live in an very very arid place--I'm talking about humidity so low that it rivals the Sahara Desert.  I hang mine for at least 4 days and then still have to burp the jars.  No matter what it may seem like, there is still a lot of residual moisture left in bud that has only hung for several days.


----------



## PencilHead (Oct 22, 2014)

Come on, boys and girls, it's fact that you won't get more than 1/3 dry weight compared to wet, green stuff.

And one thing I do miss not hanging around here much anymore are these grams per watt claims. HeeHeeHee.


----------



## umbra (Oct 22, 2014)

I do not for the life of me understand why yield is the most important thing to new growers, learn how to grow dank first. Yield will come as you fine tune your skills and appreciate good genetics. Why is lots of swag so important?


----------



## bwanabud (Oct 22, 2014)

umbra said:


> I do not for the life of me understand why yield is the most important thing to new growers, learn how to grow dank first. Yield will come as you fine tune your skills and appreciate good genetics. Why is lots of swag so important?



Umbra knows...learn to grow first, the weight will come later.


----------



## Locked (Oct 22, 2014)

I honestly have never really cared about heavy yielders.  I will always choose quality over quantity. Then again I only grow for the wife and myself, so I can afford to think that way. 
There will always be room in my tents for Low to Medium yielding Straight Fire.


----------



## Riddleme (Oct 23, 2014)

I never worry about yield as I grow/breed for myself but when I wrote my first book I made a claim in the grow part that I was gonna show patients how to get a pound from two plants, this due to the medical plant count restrictions here in Colorado. I missed it by 7 grams LOL but they got the idea, I think 

View attachment happy.jpg


----------



## yooper420 (Oct 23, 2014)

My first grow, when I didn`t know squat, and used bag seed, was my highest yielders. Two plants, 5 oz off of one and 6 oz from the other one. Grow for wife and myself. Much more concerned with quality verses quantity. Must be doing something right as the only oz`s I sold was to a dispensary I bought the seeds from. Peace and great growin`.

PS,
I also use Boveda humidity packs in my jars of stored weed. IMO, really helps.


----------

