Quote Originally Posted by RackitMan
Here is something very confusing to me. Many LED proponents loudly proclaim the need for 460-470nm red LEDs over the cheaper 630nm LEDs. I understand that this better coincides with the chlorophyll B absroption peak.

So far so good.

LEDs veg very well given appropriate wattage & color.

So far so good.

LEDs do not compare (generally) to HPS flowering as far as yield. (Please - let's not go off in that direction here. Thank you!)

OK, here is the enigma: HPS has a ton of yellow. No LED grow lamps contain yellow. HPS has lots of orange. Some LED lamps contain a little orange. HPS has virtual no Deep Red or Far Red and do very well - yet this is somehow necessary for a good flowering LED light. Even 'inferior' 630nm red is relatively low in HPS.

Any SCIENTIFIC opinions on this major discrepancy?

The only thing I can come up with is that plants rapidly adapt to the core frequency of the light provided which would put in question the whole currently accepted Plant Absorption spectrum.
for one 460nm is blue 630nm is red and 660nm is deep red:jointsmile:

so my advice here is to look at my LED's which have 3500k warm white that do appear yellow to the eye and look at my grows! :smokin:

i get great yields for the wattage i put over my plants...but the difference in my units are they use 3w diodes..not the 1w UFO style!

plus the pattern of LED''s are spread out over a 4" x 40" window creating light from many different angles!

too many folks get caught up in the more power of a single panel and applying the same thought as HID...1000w is better than 400w...in LED's it is all about the quality and power of the LED and having a good distribution so you can keep them as close to the plants as possible. This does not work with a LED panel that has all of the LED's bunched close together like UFO or similar lights....if you lower them close it shrinks the coverage so you have to lift higher to increase the light footprint and then lose effective flowering...this is why many say LED's do not work in flower and it is only because of design.

Since i have been flowering with my LED's it has increased the oil prodution and has made my meds more potent...i would love to get my meds analyzed for THC/CBD and CBN ratios because i can feel the difference in my meds. I had spinal cord injury and suffer from severe neuropathy and most peoples meds do not even touch my pain...so i will NEVER go back to HPS!:thumbsup:

plus no heat...no bulbs to buy again...my lights will pay for themselves in energy savings alone.

i have finished 3 grows to completion with yields of 390gr 437gr 357gr with 450w of LED's... the 4th will be tallied in about 2 1/2 weeks:jointsmile: