Quote Originally Posted by Heavy H
Maybe I should have made this a bit clearer. I'm an experienced grower looking for some very specific information - which plants will grow well at very high wattages.

Actually, a 600 watt lamp with a greenpower bulb ( the newest generation agricultural bulb from Philips, not street lightning like some people use ) _used just on under 1m2_ will give buttloads og light, much more than average. Sure 600 watts for a grow several square meters isn't a lot, but then again, I have several 600 watters. :-] Light usage schemes go something like this ( from memory ):

30.000 lumens/m2: Minimum for growing compact buds.
50.000-80.000: Ideal for most plants.

Above that you have diminishing returns on number of watts per m2, then you have a stage where plants are actually hurt by excessive light, and then you have a stage where you kill your plants from all the light ( try putting 0.3m2 of seedlings under a 1000 watter and see what happens ).

Grapefruit ( 90% sativa ) is only 8 weeks. I'm growing it now, and it looks good. Sure the bottom branches have small buds, but I cut most of them anyway. It's very practical for keeping airflow under the plants, I have an extra oscillating fan there. But yeah, I considered some more extreme sativas like Neville's Haze and Neville's Haze x Zamal, but they were just too long too flower.

s12fever:Your "mate's" plant look great, good luck!

So my question is which kinds of plants can profit from the levels of lumens that usually either hurt the plant or just don't give a lot of extra buds compared to more normal levels of light.

Some people say sativas because they grow in tropical areas, and they have the most light. However, a lot of indica's grow in mountainous areas where the sunlight is much more intense than at groundlevel. So really it's hard to tell.

As I stated before.....the more lumens the bigger and denser the buds. There is no strain that says "oh, not that much light"! Remember you are trying to replicate the sun and if I recall correctly the avg tropical sun emits like 10,000 lumens per square foot. In a square meter thats approximately 90,000 lumens. The only thing with more light is increased heat output (wattage). If you can 2000 watts on one plant that plant, no matter what the strain, will grow bigger denser buds. I'm sure there is a point where growth rate is maximized and diminished returns is apparent, but this is not a point that most growers reach or are even aware of, if at all. Basically, the more light you can provide the better yield will be had.