Grams Per Day: Determining Cannabis Yield Success by Weight

[Rider509]

I read an interesting article by Ben Burkhardt, who once owned the largest indoor grow facility in the country. He found that there was no simple metric for yield analysis which took into account not only the power used by lights but also the length of flowering time. Often yield is stated as grams per watt, but that doesn't take into account the difference between a plant that finishes in 45 day versus a plant that takes 90 days. He put forth a metric that takes both into account and works for the closet grower as well as a huge commercial grower, and returns a number that can be compared across any grow type.
The equation is as follows: Yield in grams ÷ number of 1000W lights ÷ days in flower = GPD average.
As an example, my three plants were under 1600W of leds and took an average of 90 days, and yielded 3000 grams of dry flowers.
3000g ÷ 1.6 ÷ 90days = 20.8 grams per day.

Here's a link if anyone would like to see the source material.
Grams Per Day by Ben Burkhardt.

 

[Derbybud]

Good read. So according to Ben you killed it.

 

[JustMeds]

A nice KPI

 

[InTheShed]

Good find Rider!

 

[BigBearNTexas]

So....this basically says that unless I get 2.5 oz per Auto, I’m having crop failure.

 

[Marzbadrock]

Good post Rider! Can even go further n figure how many gram per day per watt then figure your electric usage n figure out exactly how much it costs to grow every gram.

 

[PurpleGunRack]

Nice one, but I must say I judge crop success on a lot more than just weight and often find that the strain that yielded half of the top yielder in a grow is better on all other parametres than yield

I think price per gram says much more than g/w and g/m2, I usually factor in everything in a spreadsheet, but it lacks the abstracts such as effect and terpene profile which are the most important to me, but it's still fun to see how things stack up.

economy+stats1.png

• PurpleGunRack
• Mar 5, 2018

 

[Rider509]

Yer one of them thar Commanists aintcha, PGR. As in pi = 3,14159265359. Dadgum Commanists!

But I dig the spreadsheet... 'cepting fer the commas. LOL.

 

[Rider509]

Good post Rider! Can even go further n figure how many gram per day per watt then figure your electric usage n figure out exactly how much it costs to grow every gram.

Do we really want to know that, Marz? I prefer blissful ignorance of how much I spend.

 

[Rider509]

So....this basically says that unless I get 2.5 oz per Auto, I’m having crop failure.

From a commercial grower's point of view, yes. But us hobby growers just smile and wave as we drive by the people standing in line at the dispensary.

 

[Marzbadrock]

Do we really want to know that, Marz? I prefer blissful ignorance of how much I spend.

As a hobbiest it really makes no difference to me, I just know my $1000 a month habit costs nowhere near $1000!

 

[Marzbadrock]

But if it's gonna be measured it should be measured as much as possible lol

 

[PurpleGunRack]

Yer one of them thar Commanists aintcha, PGR. As in pi = 3,14159265359. Dadgum Commanists!

But I dig the spreadsheet... 'cepting fer the commas. LOL.

Yes, and proud of it! Metric since 1907
You Anglish imperialists can't keep us down with your obscene punctuation and undividable units of the past

 

[InTheShed]

Yes, and proud of it! Metric since 1907
You Anglish imperialists can't keep us down with your obscene punctuation and undividable units of the past

And yet you're calculating your costs in American imperialist dollars!

 

[PurpleGunRack]

It's been through a currency exchange mod for you guys

 

[Rider509]

Yes, and proud of it! Metric since 1907
You Anglish imperialists can't keep us down with your obscene punctuation and undividable units of the past

Coffee almost came out of my nose!

 

[InTheShed]

It's been through a currency exchange mod for you guys

You should at least change the formatting on that cell then so it makes sense!

Just out of curiosity, how would you write this number so it was easily readable:
32,450,657.521
?

 

[Rider509]

32.450.657,521? It looks like code for a nuclear launch.

 

[PurpleGunRack]

You should at least change the formatting on that cell then so it makes sense!

Just out of curiosity, how would you write this number so it was easily readable:
32,450,657.521
?

Swap the commas for points and vice versa

 

[gr865]

So see if I have this correct. I am running two 315W CMH's, so that is 630W. That is 0.63 of 1000.

So my formula would read, Yield / 0.63 / Days = G/day.

686/0.63/63 = 17.3 gram/day.

Is this correct?

GR