Yield Formula for Newbie's [figuring out how much you'll get...]

Newbie’s always seem to want answers… Here’s one on your Yield

You are new to growing… You know what it cost to buy…

How much can a new grower yield ? Do not believe claims on Nutes/Seeds/Growers guides, everyone that estimates what your yield will be is guessing , and they assume, you have a horticulture genius as your partner, and in that case, you wouldn’t be hanging out in the newbie section, asking yield questions-LOL…

This formula will help give you approximate yield info [rough estimate not breaking down the grow mediums, this info is just used for your guessing abilities…]
all types of medium, for first time growers…This info, may also help you choose your lighting, and how long to veg...

FORMULA: Plant x [Veg time in days x 3] divided by Light Factor “F” = Yield [G] in grams…

P= How many plants up to 4
V= Veg Days up to 63 [multiply that by 3]
F = Lighting Factor [see below]
G= Grams yield

Lighting Factor, explained here:
CFL Less than 47 watt = Your factor is--> 10
CFL 69 to 93 watts = 9
CFL/Fluorescents 93 to 230 watts= 8
CFL/Fluorescents 230-350 watts = 7
CFL/Fluorescents HO 351 -600+ watts= 6
400 watt HPS = 5.5
600 watt HPS = 5
1000 watt HPS = 3

Example: Two Plants veg for 42 days under a 400 w HPS: Formula

P (veg days x 3) divided by Factor 5.5 = Yield in Grams
2 (42 x 3) / 5.5 = G
252 / 5.5 = 46 grams

Now just change your light to a 1000 watt HPS
And do everything else the same
2 (42 x 3) / 3 =G
Yield = 84 grams

Veg longer = higher yield…
More plants up to 4, more yield…
Bigger lighting = more yield…

There are so many more determining factors in yield...Your yields may vary…
Remember this is “The Newbie” guide, and it is approximate…
Long time growers will obviously get more…
And Newbies, If you do everything correct, you could get more/way more...
...Good Luck Growing !

Seems really conservative to me. Running my numbers yields less than .25 g per watt. I don't think it's possible to reduce yield to a mathematical formula. Way too many variables.

humidity, strain, watering schedule, nutes and nute formula, nute application, hydro?, soil?, light penetration, square footage, etc, etc...

but I see what you're getting. Geez, i know when I started learning this stuff i was asking the same thing "well how much will i get???" You think I ever got an answer? But this should appease any newbies and give them a good target to work towards.

Nice formula. nice... very-roughly-approximate formula. consider it a ball park.... a very big ball park

Remember Newbie has to have a first grow, these could be target numbers, they could make with ease...

I think, not trying to be exact, however, just with getting better lights, with all else equal, you will harvest more...


There is nothing that is exact...

Yeah light intensity = harvest

0.75 grams per actual watt is a good initial goal and a good place to be. 0.50 grams/watt is a cakewalk.

You think the average new grower can easily get .75 gpw? Or even .5? Im not so sure about that.

Cool formula, didn't work out for me. Not even for my first grow, according to that I should have gotten around 21 grams. First time around I got 34g. With my current setup I should get around 19g.. Last grow I got 184g

I know you said it's for newbies but your math IMO is a bit off even with beginners considered.

Shivaskunk said:

You think the average new grower can easily get .75 gpw? Or even .5? Im not so sure about that.

Click to expand...

Half a gram/watt is no big deal. "Average new grower" is the kicker. There's lots of first time growers on here that have done their homework and kicked ass. Others with 6 grows and it's obvious they need to find a new hobby.

AimAim said:

0.75 grams per actual watt is a good initial goal and a good place to be. 0.50 grams/watt is a cakewalk.

Click to expand...

I agree, if you don't get at least 0.50 gr/watt something went wrong "and" you didn't fix it (with the help of Riu for example).

I Just ran the math and I got about 1.2 grams per watt in flower and veg.
1000 watt HPS in flower and 750 watts of t-5s in vegetation in my first indoor run. I got 6 ounces out of four plants.
I don't think you can put a mathematical formula on it; there are way to many things that can happen and can be done to kill or improve production.

It was a nice thought to try and eliminate the re-asked question of the year, but I'm not sure it will work.

Of course it will not work... However now, when I see the question asked, which we all know is impossible to answer...
I will link them to this Formula...
Obviously there are too many varies in growing...
And of course a Math Formula will not solve someone like Bmeat's problems....
Ha... Have a great Grow...

This formula is completely and entirely inaccurate.

Here is my formula....

You will get between 1/4 oz and 2lbs per plant dependant on thousands of variables.

althor said:

You will get between 1/4 oz and 2lbs per plant dependant on thousands of variables.

Click to expand...

At least this is a true statement....