Alright, I've heard a lot of fighting over which is better to use during vegging, but I want to get a solid answer and I think a lot of people would too. It makes sense that Metal Halide would be superior because of the blue spectrum that plants crave during vegetative growth, but a lot of people say they get better results from using High Pressure Sodium. So lets hear what the city has to say about the subject!
Unfortunately mother nature didn't write us a manual on the straight-up best way to do it, so there really is no solid answer, just preferences. I voted for HPS merely because it works best for me and always has, but not by a significant amount or anything like that. I have close friends who think I am crazy for this but then again, I also have plenty of friends who think the MH guys are crazy so I think it will always be debatable, especially with world famous growers still arguing it amongst each other! I think the only way to find out what suits you best is to give both a try, but if you don't want to invest in an MH lamp just "to try it out" than just roll with the HPS, you are going to need it for flower anyways. Peace
Thanks for the note, I guess the only true way to find out would be a side by side grow, one light by MH, and the other HPS. Both would have to be identical (Mirror grows) but im sure someone with better resources than I could preform this test. but untill then it will just remain a preference.
For sure. But then again different strains and in different climates contain a variety of pigments that all react to different wavelengths of light differently. Just sneak in to your old college biology lab and hit up the photospectrometer lol! Then you could use a lamp with the closest wavelength to what reacts best to your particular plant's pigment. I've been wanting to do that since freshman year! And that was about ten years ago!