Is talking about grams per watts absolutely rediculous?

[FlowerFarmer]

I'm more of a 'cash in pocket' kind of guy to determine my progress. No sense in gauging my performance if its not equating to my end objective.

Lbs per light for kicks. Lbs out the door for keeps. Any product beyond a nice round number is given away to friends or those in need.


Anyone gauging there grow by weighing dry weight - comparison from grow to grow - is leading themselves blind anyways. If you're truly looking to know if you are improving or not you need to be weighing fresh wet product. Dry weight can vary across the board determinant on actual water content and time of measurement...there is just no way to accurately compare 2 grows if you're using a dry weight to gauge...unless of course your not being very accurate about it and just figuring lbs per light or lbs achieved.

One simply cannot say that they saw an increase in X grams from one grow to another and actually attribute to anything specific.. way too many variables in gardening... and if weighing dry it's completely irrelevant anyways because one sample could still have a larger % of moisture in it then the last sample - of course unbeknownst to the grower because to them.. dry is dry.. wet is wet.. but there are many degrees in the middle of unknown.

I hope that makes sense before I start getting blasted with negative rep for talking about weighing wet cannabis to gauge weight from a grow. I'm not saying this is a figure to post on here lead others to believe you get huge yields.. but as a number for yourself to gauge grow performance its the only way to go.

Then.. if you want to continue to chart your efficiency using some g/w or g/w/month scale or whatever at least you'll be being somewhat honest with yourself.

 

[FarmerGreen]

Yep yep, that all makes sense. I was going to say it would be easy to convert kWh to dollars and add all other costs like nutes etc...then you could even figure $ per gram.
Nice to know if you're growing for personal use, I'm always trying to figure how much I'm saving by growing myself

 

[meltybubble]

Its clear some growers dont find it useful,simple dont use it.
For years alot of folk did and found it helpful also.

Cool chart!

 

[Jedi]

Thanks for that

thanks!

i was thinking about this graph specifically
http://urbangardenmagazine.com/wp-content/uploads/2010/07/VPD.jpg

View Image

 

[TREE KING]

you have to calc gram per watt so you know that your getting the proper yields or not its not just about bragging

the best way i think to do the math is a gram per watt in a 60 day period including veg. so if you have a strain that takes 60 days to flower and dont do any veg time your all set without having to do any extra calculations. if you do any veg time then you gotta calculate that in and minus off some of the yield

 

[turbo6shooter]

Weight isnt everything. Other factors like flower density also come to play.

 

[maryjanesdad]

too me it'z simple.....Did U yield enuff too cover ALL needs until next harvest.....????
if U answer Yes, then U done good enuff....
if U answer NO, then U HAVE_NOT done good enuff, and better get crAck'ing on improvements of sum sort.....
otherwise U'r just pissing in the wind w/ it blowing back in U'r face.....and chasing other peoples dreams.....

get a quality light, quality bulb, quality strain, quality nutes, water, love and some CO2 and you will grow quality all day.

shut up and grow is what i have to say to this whole gpw issue.

 

[EclipseFour20]

I dunno about grams per watt....but I do understand grams per plant! (I prefer to measure watts per square foot...which is about 55 watts/sq ft in my flower chamber).

I don't smoke "watts"...but I do smoke "whats" on my plant.

Cheers!

 

[maryjanesdad]

I dunno about grams per watt....but I do understand grams per plant! (I prefer to measure watts per square foot...which is about 55 watts/sq ft in my flower chamber).

I don't smoke "watts"...but I do smoke "whats" on my plant.

Cheers!

i was at 32w per sq ft which is not good but it worked for me.

 

[Bongstar420]

wet weight estimates are more inaccurate

wet weight estimates are more inaccurate

I'm more of a 'cash in pocket' kind of guy to determine my progress. No sense in gauging my performance if its not equating to my end objective.

Lbs per light for kicks. Lbs out the door for keeps. Any product beyond a nice round number is given away to friends or those in need.


Anyone gauging there grow by weighing dry weight - comparison from grow to grow - is leading themselves blind anyways. If you're truly looking to know if you are improving or not you need to be weighing fresh wet product. Dry weight can vary across the board determinant on actual water content and time of measurement...there is just no way to accurately compare 2 grows if you're using a dry weight to gauge...unless of course your not being very accurate about it and just figuring lbs per light or lbs achieved.

One simply cannot say that they saw an increase in X grams from one grow to another and actually attribute to anything specific.. way too many variables in gardening... and if weighing dry it's completely irrelevant anyways because one sample could still have a larger % of moisture in it then the last sample - of course unbeknownst to the grower because to them.. dry is dry.. wet is wet.. but there are many degrees in the middle of unknown.

I hope that makes sense before I start getting blasted with negative rep for talking about weighing wet cannabis to gauge weight from a grow. I'm not saying this is a figure to post on here lead others to believe you get huge yields.. but as a number for yourself to gauge grow performance its the only way to go.

Then.. if you want to continue to chart your efficiency using some g/w or g/w/month scale or whatever at least you'll be being somewhat honest with yourself.

The water content of fresh Cannabis varies from 81-89% of the dry weight. For a light, that will translate to a variation of 2-3.75oz for 1lb and 3.9-7.5 for 2lb in the dry weight estimate. That's 2-8oz of variation. The dry weight of stem snap dry cannabis can only very in water content by 3-5% of the total weight. For a light, that is .5-1.7oz total . That is much less variation. I would weigh the dry stuff with the caveat +/- .5-.1.7oz depending on the total yield and how snappy the stems are.

People that are aversive to labeling and measuring things are afraid of being losers in my opinion.

 

[Smokecraft]

What's really ridiculous is that I've seen two people spell it "rediculous"

In all seriousness though, for the majority of people GPW is a good way for them to gauge how green their thumbs are getting. Low GPW can tell someone that something is going wrong somewhere, higher GPW can tell them they are going in the right direction. If you think of it as a trouble shooting tool instead of and end goal it's uses become apparent. Of course, like any trouble shooting tool, it can't be the only one in your toolset.

That said, I don't think GPW is a measuring stick you can use with a perpetual grow. Grams/Plant might be the way to go, or Grams/Harvest possibly, but GPW gets seriously skewed no matter how or when you measure it. Let's say I'm pulling 4oz (112g) out of my cab every 2 weeks using a 600w HPS. If I measure per harvest I'm only getting .18GPW which looks terrible. If I measure every 60 days like someone above me suggested then that's 4 harvests for 16oz (448g) and .74GPW which looks great when you consider average GPW is usually around .5, but is probably not a true GPW. So using GPW for perpetual grows means you are either skewing way over, or way under. A different, more accurate metric is definitely needed.

 

[GMax]

i was talking about this in another thread... maybe you find this relevant...

6.5 lbs really doesnt seem that difficult when you are running 300 plants... you only need less than 10g per plant to hit those numbers.. with the right strain that shouldnt be difficult.. i am interested in finding out few more details about this guys setup^

sometimes comparing yeilds is like apples and oranges though...if I veg plants for three months and flower them out for 70+ days and yeild 10 lbs that is impressive..but am i yeilding more than someone running staggered crops and bringing in 2 lbs a month..no..

I am a believer that the gpw is a outdated way to measure yield success .. Even if you could eliminate veg altogether the flowering times can still make a big difference ..

Assuming that there is no down time.. You harvest your plants and fill back up same day

FLOWER TIME / YIELD / CROPSperYR / TOTAL

12 weeks ///// 6.92 lb ///// 4.33 /////30lbs

11 weeks ///// 6.35 lb ///// 4.72 /////30lbs

10 weeks ///// 5.77 lb ///// 5.2 ///// 30lbs

9 weeks ///// 5.19 lb ///// 5.77 /////30lbs

8 weeks ///// 4.61 lb ///// 6.5 ///// 30lbs

7 weeks ///// 4.04 lb ///// 7.42 ///// 30lbs


The grower with the 12 week strain is hitting 1.72 gpw..while the grower with the 7 week strain is hitting 1 gpw but neither grower is growing more than the other …and that is almost 3lb difference in yield!!

Start adding in actual veg times and it whole nother story and you can see how it starts to become a complicated comparison

Right now my best numbers is 3lbs with a 7week strain ( which by this comparison is = 3.85lbs with your standard 9wkr) but I am regularly hitting 2.5-2.75.. Still not really where I wanna be but it respectable and I am happy with the consistency of it, plus the effort vs reward is ridiculous …I am expecting better things from my v2 with increased plant numbers and more space per plant etc.. I plan on hitting 4lb(7wks) with my first crop and dialing from there

They say Time is money..

 

[junior_grower]

Well GpW used to be my measure. That all ended when I became a Dg. I calculate production cost to the gram. Its simple really, add up everything ( lights, fans, pumps, Controllers). My grow consumes 74.5kWh per day in flower, and 1.08kWh per day in veg. I add up days in each, divide by grams produced. This along with nutes, Co2, labor, Misc expenses is added up to give a Cost per gram.
My last grow cost me 1.22 cents per gram to produce, ( labor paid @ 75$ day).

 

[Smokecraft]

Well GpW used to be my measure. That all ended when I became a Dg. I calculate production cost to the gram. Its simple really, add up everything ( lights, fans, pumps, Controllers). My grow consumes 74.5kWh per day in flower, and 1.08kWh per day in veg. I add up days in each, divide by grams produced. This along with nutes, Co2, labor, Misc expenses is added up to give a Cost per gram.
My last grow cost me 1.22 cents per gram to produce, ( labor paid @ 75$ day).

That's a great metric for commercial growing for sure, those growing for personal or medical reasons may not find as much use out of it though. As long as I produce enough medicine for me and the two other people I'm helping I'll be satisfied. An ounce around here is about 320$, as long as we're running cheaper than that we're set, so in my situation a gram per harvest measurement would suffice.

That's another thing that needs to be taken in to account, the needs of the grower. My situation doesn't require highly accurate measurement methods, but others like yourself probably do. So really what's best is what works for the person growing.

 

[supermanlives]

grams per watt is only good if ya take into account veg time, and all electric. if one grower uses 1000 watts and an ac and another just a light and no ac all things being equal the grower without the ac wins. got to take into account all electric. and dry weight is fine. use a hygromemeter to get moisture levels so all weed is dried to the same level.

 

[Bongstar420]

That's a great metric for commercial growing for sure, those growing for personal or medical reasons may not find as much use out of it though. As long as I produce enough medicine for me and the two other people I'm helping I'll be satisfied. An ounce around here is about 320$, as long as we're running cheaper than that we're set, so in my situation a gram per harvest measurement would suffice.

That's another thing that needs to be taken in to account, the needs of the grower. My situation doesn't require highly accurate measurement methods, but others like yourself probably do. So really what's best is what works for the person growing.

Should'nt "medicine" be subjected to stricter standards than that?

 

[tenthirty]

GPW is good for measuring a given methodology over time.
What I am finding is that the limiting factor is grams per given area.

You can only cram so many budsicles in a given area.

Now what the most efficient power consumption is for a give area????

 

[BrnCow]

How would you measure such a big amount and dialing in would be a real bastard on a yearly basis...

 

[hurdy gurdy man]

Grow a potent strain that does well in your conditions that meets your needs.

Grams per watt only deals with 2 variables in a multivariable process. It does provide a very general common reference point, however.

Plant count; watts per square foot; veg time; hydro vs. soil; length of flower time; potency; all major variables that have a big effect in the final outcome.

 

[mojave green]

Gpw is a shitty measurement, doesnt account for varying lengths of the veg and flowering cycle.

It makes more sense to measure grams per kilowatt-hours used from start to finish.

and those kilowatt hours should include ventilation, a/c, pumps etc, no?