The way I understand it if you can get 1/2 gram dry for each Watt, it's considered a good grow. It's not the number of plants, it's the space that the plants use that's important.
This guy hit it on the head.
If you fill up the alotted space under your light you can easily get 1 gram per watt.....of course you need very good conditions.
You can do this many ways with a different amount of plants.
Let's use a 1000 watt as an example. With proper reflection in an enclosed area the light will cover a good 5 x 5 area max. You can put 4 wide ass bushes under it in 7 gallon pots.....or you can go sea of green and use 25 single cola plants in 2 gallon pots.
The idea is to use ALL of the area under the light. Make sure your plants grow into an even canopy under the light and cut off all branches that don't make it. If all the branches are within 12" in height of each other you got it made. A 1000 watt will penetrate deeply enough so the whole canopy grows evenly (if using clones).
Scared of getting caught with a lot of plants? Grow 4 giant 2' tall by 2' wide bushes and put them under a 1000 watt hps. If done right with proper care and maintenance you will get at least a pound.
That's .5 grams a watt. You can do this with your eyes closed. A semi pro can get 2 pounds out of 4 plants like that....probably more.
Remember this...an even canopy will grow huge colas in abundance because they are all getting major light. Try it...you may like it.
This also goes for the 600 watt ( 4' x 4') and 400 watt (3' x 3') hps lights. Use your area right, feed em, water em and keep it clean and you can do this with ease.
Now you may go and say to yourself "Wow, this guy hardly posts. What could he know?"
A lot more than you may think
