So by now you made your choice on a set up you prefer by budget, time, & space this is where you grab your light. You’re probably thinking mh metal halide, hps high pressure sodium, florescent, or leds. When it comes to this intensity is key for bigger. That being said hps is the most intense & grows the fastest in vege (in the root area more than in the green area) & the biggest. MH is less intense; you can even say it’s a lower hps because even though it shines blue to your eyes it is still basically orange in spectrum. Just as an example let’s take 600 mh it has 50000 lumens and hps has 90000 lumens. Lumens equal intensity. This means mh is going to grow slower and stretch more than hps. So in the same time the mh plant will be shorter and have less internode (budding spots) than hps. That being said there are times to me that mh is cool to use & that is the last two weeks of flowering (the flushing period) because the plant doesn’t need as intense light then because it’s not using as much food or photosynthesizing light as much. Another time is if you want your vege to slow down a bit because your bloom has to still finish & make room. Try and find a mh bulb with more blue in its spectrum.
When it comes to fluorescents you can use it for cloning only. I recommend it only if you have a one light set up & you want to clone. Other than that throw clones in side light. Side light is the low light in corner coming off your big light.
Leds. These are good for supplemental lighting, meaning these lights should be used in conjunction with hps/mh. When buying these lights make sure that you can get a 3-5 year warranty on them because a row or two of lights can go out on you. From my experience & experiments the Procyon 100 has been spectacular in comparable close to 400 watt hps and only 100 watts out the wall. There are probably better I’m not saying I’ve seen everything. Another thing is to look for leds that are all white and meant to grow because all white light is all colors of the spectrum.
There is also an induction light comparable to fluorescents but uses less watts & has a great spectrum of light for those like I said earlier who want a slower growth rate. These lights grow very pleasing to look at plants due to the spectrum of lighting.
Another light to look into is plasma. This light can possibly be something due to its heavy blue spectrum output. Right now I haven’t seen one on the market that has high lumens output. I will continue to look into this because LG seems to have one that might be there for us. More on that.
With all that being said there is nothing better than the sun in intensity and spectrum. Having the sun also increase better THC, cbd, cbn, and all terpene production in marijuana plants. In review for the best light you want intensity (high lumens) and a good spectrum all colors during the whole grow operation.
On a side note the light builds a virtual frame. What I mean if you take a 400 watt and a 1000 watt light and vege for 1 month your plant from the 400 will be about 1 ½ -2 feet tall and your 1000 watt light would be about 3-5 feet tall. This is because the 400 watt is made to put on 400 grams and the 1000 watt is built to put on 1000 grams.