What about using all blue light for the flowering transition?
What about blue light for the ripening?
Say, use double the light in red for four weeks in the middle and two weeks at the beginning and two weeks at the end in blue.
I've noticed differences in red and blue light with this process. Now I'm testing to see if I can save some money on half of my flowering cycle.
Your thoughts?
My thoughts are these: why would anyone try to save money on power if it impacts yield? It is only going to cost you more in the long run.
There is a law of diminishing returns which says you can add more light, but you won't get more yield - the plant can only photosynthesise so much (it can also be counterproductive by inducing heat/light radiation stress). What you are trying to achieve is to make your grow as efficient as possible, so that your plants have enough light but - most importantly - you make use of all available light (energy) that you produce as a grower. That means even light distribution, maintaining plant health, and - the most important factor - maintaining your root zone. An efficient root system is the key to fast growth - which is why aeroponics > NFT > DWC > coco > soil etc.
But here's the kicker: you want reliability.
An advanced aeroponic system will kick just about any other system's arse. But it must be maintained properly, which means checking for nutrient blocked misters, drains, pump pressures and optimum timing cycles etc.
One pump failure, and you potentially lose your entire crop. Aeroponics doesn't look so good after that, does it?
I have had pump failures. I have had timer failures. I have had power failures. I have had most failures! Which is why I eventually switched to coco run-to-waste using organic nutrients. A pump failure in coco still gives you a fighting chance, as the coco media retains moisture and there is a good chance you discover the failure before your plants die. Organic-based nutrients have always produced the best results for me and, anecdotally, my friends all say it tastes better.
But I digress . . . Back to your original question. What you are proposing has been done in the HID world using a mixture of MH and HPS. I used to do it myself, vegging under MH, then running MH the first two weeks of flowering to reduce stretch, then adding HPS - using a ratio of about 2:1 HPS:MH - and then finishing the plants off with HPS.
It comes down to two factors: do you have the time to mess around with all this? And if so, do not ever think that spectrum > total light. It isn't. You want your plant to have as much light as it can handle. If the quality of your light is poor, or the spectrum is off for that particular cycle, then you just need more of it.
The trick is certainly tailor your spectrum to the plant cycle, but don't deprive the plant of light intensity in the process.
As a general rule, red light sources such as HPS (which I'm not comparing to LED here) will produce greater flowering yields. This has been proven over and over again. Blue light sources such as MH will reduce internodal length and promote tighter bud structure, but with slightly reduced yields. A combination of the two - and that includes CMH - has been found to be a good compromise. But pure HPS in the last 3/4 of flowering has always proven to produce the best yields.
If you can apply that knowledge to LED growing, then learn from the HID boys who have been dong this a long time. Personally, I believe full spectrum with lots of red and a small amount of UV (A and B) to emulate the autumn/winter sun is what should work best during the full flower cycle.
