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how much yield can you pull from 600 HPS?

  • by johnjohn
  • Aug 12 2010 02:27 AM
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Posted 12 August 2010 - 02:27 AM

In my last grow I had a lot of space, horizontal and vertical, and had 7 plants under hps. I think that resulted in about 18 ounces, something like 2-3 ounces per plant. What i realized is that the plants could have yielded more but they were fighting for light space.

I wanted the lights to be kinda close to the tops of plants so there would be more vertical penetration, plants where 3-4 feet high, but closer to plants means less horizontal penetration.

Because I think they were fighting for light, I think I could have pulled the same yield from 5 plants, just more ounces per plant.

What do you think about this, is it correct to calculate yield on the basis of light penetration. I topped, fimmed, and did lots of lst which the plants loved, so I am not talking about strategies for more yield, just thinking about the relation of light to yield.

Would you have raised the light higher for more horizontal penetration, meaning, do you think that would result in more yield?

anyways, back to the most important question, how much did you yield from your 600 HPS setup?

p.s. this was my grow:

Posted Image

Edited by johnjohn, 12 August 2010 - 04:17 AM.

Replies (9)

  • Couple of Cannabis lovers

  • CannabisCouple
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Posted 12 August 2010 - 04:47 PM

I am i interested to know as well.. I am going 600 and I want to do a SOG with 16 getting two off each hopefully...

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  • colafarmer
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Posted 12 August 2010 - 07:08 PM

Lighting is a key factor in any grow. Strain and how well you care for the plants determines yield as well...
MH/HPS has better penetration than fluorecents and cfl's but with the proper setup of cfl you can acheive a nice yield if you don't starve the plant of light....


  • smoove
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Posted 12 August 2010 - 10:26 PM

lol @ colafarmer... did you even read john's post?

John, that's some good insight/observation, and I think probably just as important to dial in as any other factor in your grow. I think it might mostly be determined by the type or even brand of reflector (if any) you're using. Generally I think there is a point of diminishing return when it comes to raising your lights. While yes, you are creating more spread when you raise your lights, you're also loosing both light intensity to the tops and penetration through the canopy.

Personally I go for more penetration than spread and I think reflective grow room surfaces can make up for the loss of horizontal spread when keeping your lights lower.

Something else to consider, I'd imagine there are instances where wide spreading parabolic reflectors would be more appropriate for a space than a narrow spreading directional reflector, like SOG grows in wider open grow rooms.

I just moved up to a 600W and haven't flowered anything with it yet so maybe I shouldn't have replied to this... but too late for that :smoke:

But with my 400W I was pulling close to 14oz. with 2 plants in a confined 2' X 3' growbox.

Edited by smoove, 12 August 2010 - 11:05 PM.

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Posted 13 August 2010 - 12:56 AM

392 g's... thats almost 1g per watt thats great smoove

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  • geoffofmse
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Posted 13 August 2010 - 05:51 AM

392 g's... thats almost 1g per watt thats great smoove

he said 600 watts how is that 1w/pg? lol maybe off a 400 watt i got 189 grams off of a 150hps and 2 40watt warm spectrum cfls of purple widow off two topped plants vegged for 51 days :smoke:

Edited by geoffofmse, 13 August 2010 - 05:53 AM.
stoned forgot to add veg info hahaha

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Posted 13 August 2010 - 07:42 AM

how big is your grow space?18 z's isnt bad off a 600.i havent had my 600 long enough to give good numbers.i go perpetual and have been trying new ways.trying a modular scrog now i had to make my scrogs smaller then i would like to fit my veg cab.i can fit 8 in my tent and have been putting 2 every other week in.by scrogging i keep the light high enough to cover my plants in a roughly 40 by 40 inch tent.with the screen 14 inches high andd the flowers about 6 inches over screen my 600 air cooled is about 12 inches above canopy

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Posted 13 August 2010 - 01:09 PM

thank you all for the responses, 14 off 2 plants is real nice, but I wonder if you would have increased the yield if you grew 4 plants in the same setup. My room size was 6x7 feet but the hps spread was probably 4x3 feet.

Maybe I should get another 600 or add a t5 to current hps.

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Posted 13 August 2010 - 01:13 PM

Rule of thumb for experienced growers who have their grow op dialed in is target of 1gram per watt, so 600 watts = 600 grams = about 21.5 oz.

To get there, I suggest using MH for vegging and replacing those space blankets on your walls with horticulture-grade mylar.

You are thinking right about having a flattened canopy that gets more light intensity to more of the plant.

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Posted 14 August 2010 - 03:46 PM

i do use MH for veg and interesting that you say to replace space blankets with horticulture-grade mylar, is there a real difference?

21.5 ounces would be a sick yield, i might be able to pull it off by vegging 2 more weeks, fimming instead of topping, and then setting up a nice scrog for flower.

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