Yield per Watt

[Landing]

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]

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]

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]

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?

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]

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

 

[zem]

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]

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]

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.

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:

here

33oz cured (924g)
600w
1.54gpw

x9 Kaliman Cheese

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?

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?

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.

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.

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.

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]

here

33oz cured (924g)
600w
1.54gpw

x9 Kaliman Cheese

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

 

[Landing]

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]

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]

Only if it was cured with lead.

:rofl:

 

[goats_head_soup]

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]

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..

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.

My Bubble hash
My picture

Oh, I thought it was a seed.

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

 

[Landing]

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]

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]

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]

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?

What he said above is correct.

 

[Landing]

What he said above is correct.

Who? Me or the other guy?

 

[Locked]

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.