SupraSPL
Well-Known Member
Maurice here is a thread with some DiY LED vegging info.
From an earlier post: "Photosynthetic efficiency has two aspects. One is the fact that individual photons drive photosynthesis and since blue photons require more energy to produce, they are a less efficient way to get the job done than reds. Therefore we use as little blue as is required to get the job done. KNNA recommends 25-30% for vegging and 15-20% for flowering (PAR Watts) and I agree with his recommendation. Luckily for us, blue LEDs are the most efficient there are so, that makes up for it (Luxeon ES M4R is 55% efficient at 700mA). From my experience, adding deep blue to HPS increases trichomes, terpenes and maybe even cannabinoids (speculating). 3000K LED may benefit from some extra blue, especially the Vero.
Second is more of a speculation that blue and red photons are more efficient than green/yellow because the leaves absorb the blue and red/deep red much better. We used to think this would give LED an additional 25% advantage over HPS, but in practice it may not be quite that much after all. That said, I do believe there is some photosynthetic efficiency advantage over HPS and that adding the reds/deep reds makes buds denser and finish faster (speculating).
Regarding XML2, they are the most efficient non-COB whites, but they are not as efficient as COBs. I like the XML2 for vegging though because they can spread out their wattage better than COB and we dont need nearly as much wattage during veg."
So you can use cool whites, neutral whites, red/blue or red/white/blue. There are lots of ways to make a vegging light that can fulfill the 25-30% blue guideline.
From an earlier post: "Photosynthetic efficiency has two aspects. One is the fact that individual photons drive photosynthesis and since blue photons require more energy to produce, they are a less efficient way to get the job done than reds. Therefore we use as little blue as is required to get the job done. KNNA recommends 25-30% for vegging and 15-20% for flowering (PAR Watts) and I agree with his recommendation. Luckily for us, blue LEDs are the most efficient there are so, that makes up for it (Luxeon ES M4R is 55% efficient at 700mA). From my experience, adding deep blue to HPS increases trichomes, terpenes and maybe even cannabinoids (speculating). 3000K LED may benefit from some extra blue, especially the Vero.
Second is more of a speculation that blue and red photons are more efficient than green/yellow because the leaves absorb the blue and red/deep red much better. We used to think this would give LED an additional 25% advantage over HPS, but in practice it may not be quite that much after all. That said, I do believe there is some photosynthetic efficiency advantage over HPS and that adding the reds/deep reds makes buds denser and finish faster (speculating).
Regarding XML2, they are the most efficient non-COB whites, but they are not as efficient as COBs. I like the XML2 for vegging though because they can spread out their wattage better than COB and we dont need nearly as much wattage during veg."
So you can use cool whites, neutral whites, red/blue or red/white/blue. There are lots of ways to make a vegging light that can fulfill the 25-30% blue guideline.
