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Inside the Groundbreaking Farm That Boasts Three Pounds of Cannabis per Grow Light

Here’s the book they published on their method:


Let’s get a press review copy!

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From how many square feet, including all phases of growth, in how long a time. The only valid way to compare dissimilar techniques and/or technologies in cannabiculture is the 30+ year old "Segal Formula."
Grams of salable product per year divided by the area required to produce them.
G/ft2 or m2
From there you can derive the other important information like: g/KwH, G/$ROI, etc.


I will be surprised if they kick down a copy of the book they sell for $420 each.


There are a couple of other calculation models that should be included. I will pull up a bunch of modeling methods. It’s fun to put them side by side. Drives the bankers analysts nuts.

I saw a news out of Germany, the Netherlands and Israel from of all places an Electrical Generation publication. That took into account the The energy cost based on the Co2 foot print of the KWH foot print when calculating glasshouse production. There are some great papers out of Japan on growth pay back curve functions that use a funny form of algebra to illatrate different payback models, this is in the journal of applied mathematics in the early 2000’s. We used them IPO calculation for two tech companies going public. Then some guy from Iceland proposed a method using geothermal payback models. Truely bizarre reading.

Somewhere i have some spreadsheets with bizarre ROI methods too again to drive high paid analysis nuts.


Would they as effectively give an accurate way to calculate yield for comparison of dissimilar techniques and/or technologies? IF so, how was yield calculated?

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That is the fun of yield calculations. As my father said “there are lies damm lies and statistician. “

Yes the nice thing about using multiple calculation techniques for things like yield. Is you can find flaws and similarities in the method used.

This gives the grower or analyst a way to cross reference the variably of the inputs used.

The bottom line for use different analytical methods, is like turning a painting upside down in order to view it in a new way. You see color and shapes instead of trees and Lilly pads.

It merely a tool in our kit as growers and businesses people. If we do thing the same way as our fathers fathers we would not yet have the wheel.

From the voices in head


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The worst thing they can say is no. I am no richer or poorer for asking.

They on the other hand have the potential of a good review and more potential sales.

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Maybe so, but on a non intellectual-exercise, bottom-line, business basis no other formula allows accurate comparison of dissimilar methods and/or technologies to determine which results in a higher yield, which is why it is what smart
commercial cannabiculturists have used since I first proposed it in Sinsemilla Tips 30+ years ago.

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I hope they give it to you. Being given or loaned a copy is the only way I’ll ever get to read it.

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I have found turning ideas on there head, And exploring new methods often give surprising results. For example glasshouse for years used a standard queuing calculation called a straight line queue, for production yield calculation. But, with the advent of computers we could use a matrix deferential queuing method to calculate production yield benefits. You could do in minutes what would take years using pen and paper. It proved that if a grow grew x percent less of poinsettia they could grow y percent more of a valentine day crop and improve overall cost efficiency via a higher yield.

This is just an example.

The question always both an intellectual and non intellectual argument.

If verity a gives you x amount of a desirable component and y gives you half of the component. But, y grow in half the time than x. Which gives the higher yield?

Using the method you illiterates earlier they are equal. But, what if you could also account for other veritable input characteristics? Labor requirements for two crops verses one. What if crop y was diseases resistant. That would mean lower inputs. What if crop y was more photo efficient? Could you have lower light requirements.

Wolf, See what I am leading too? We have more tools in are kit.

All of those things you mention require an accurate yield figure as a base.

Yield/ft2/time is that basis.

Just an FYI the Segal formula shows up under a different name in a publication by for Sweetpea production field notes by by L H Bailey in 1896

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yield/$labor/= $labor per gram.
None of it is accurate without an accurate yield figure which is VALID. This is why I’m an applied photo-biologist rather than a theoretical one. I must have real world figures for what I tell a consultee to be meaningful.

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Oh well, I guess I’ll give him his due and call it the “Bailey Effect.”

I will look up the book, if I recall he was referencing an older publication. Could be from Atlee Burpee he was big a figure in early commercial production. Or from Geo Ball, they both wanted to make glasshouse production profitable through science and mathematics. The old Atlee Burpee writings are online.

All stuff I have on yield calculation are from a lit search from school days. Undergraduate project.

Look at this post Cost calculation for greenhouses it has two links to extension publications from Arkansas. The cost numbers are part of an ongoing study started in the 1950’s. What are your fixed overhead cost for running a greenhouse. I helped tablulate some of the data while in school and participated in the study each year I was in business.

The core number are very accurate.

Back to yield I am creating a document on ways to calculate yield for the sites library. It will be links to other documentation. And sources.
Plus links to Europeans companies that perform production analysis for growers.
Plus a bibliography to books. If you have a list of books or articles I should link to please let me know.


On July 6th I got their newsletter bragging about 4.5lb/light!

"Our nine-part product line contains all micro and macro nutrients required to produce the most grams per square foot, while achieving the highest quality possible. In a recent cycle, we tested Success Nutrients in a side by side test with leading competitors under 36-light systems. The Success Nutrient side pulled down 164.4 pounds of dried, cured flower (METRC verified), equating to over 4.5 pounds per light.

This was achieved with a less than $1* cost of cultivation per gram of dried flower.

*Includes overhead costs for nutrients, testing, cultivation consumables, general consumables, pest management, utilities (power, water, sewer, gas, telecom, and waste disposal), harvest consumables, labor (cultivation, harvest, and maintenance including all related costs and benefits), other longer-lived consumables (lamps, HVAC filters, UV lamps, etc.), cultivation management (master grower and cultivation manager), and other miscellaneous costs related to state mandated compliance and reporting requirements."

I finally emailed them this morning and asked about g/sqft. I’ll let you know what they say.


Please, Give me a paper or citation. Every fertilizer company in the history of horticulture has said there product is best.

Plants can not tell the difference between organic and inorganic sources of nutrition. They do react to different forms of nitrogen. But, this can be a function of temperature and soiless biology.

Warm water watering and a good consistent liquid feed will probably give you higher yields. Flash heaters have come down in price.


I’ve read 3# per light. I don’t particularly care for it, indeed because they are so exact with what you do, which doesn’t account for A LOT of variables that you may not have control over. Let’s not even mention the price (for very average information)! I also don’t think 3# per light is that impressive of a yield, particularly since the advent of DE HPS lights. We got 3.4 per light and the grow didn’t even look that great. Gavitas say they run at 1150w on the highest setting, though I wouldn’t be surprised if it was actually a little more… Weight per $ per year is what matters. Square footage doesn’t matter, it’s just what you’re paying for it, but I can see how that would be good for comparison to other growers looking at maximizing yield PER square foot by itself. Anyhow, now we’re growing all organic (synthetic before), and we’re still pulling 3# per light with very sub-par health. Once we lock in a good rotation of amendments, I can see 4# easy peasy :slight_smile: please look up SOIL FOOD WEB for yourself and the rest of the world. Synthetic nutrients really are terrible for everyone involved…


Gosh and now that I think about it, weight alone is a pretty foolish way to look at it, since growing nothing but the heaviest-yielding strain would be the best way to get there. You have to take into account that variety sells, and that you can get more $ for higher quality (to a degree). I think spending your time and effort trying to replicate books like 3 per light is a waste of time. Skim through it, sure, but don’t get hung up. I guarantee they don’t have every variable under control, just like anyone else…