I run mine with the hps on the hps timer but I'll warn you that they can experience negative symptoms from a ton of long uvb from having none. This is definitely part of hardening off plants that you put outside(the extra uvb exposure). What i do is start them at the roof and lower them to 18"-24" away from the closest top. I used to run them only at the end but now i feel that the plant will try to progressively create more thc as the uvb exposure increases. I also cut them on the last day with the idea that the uvb won't be there to break down the thc for that day so it should be at peak level when harvesting. I have no scientific proof to either of those but that's what i hope is happening lol. Plants do funny things when you give them too much uvb. For example, they will pray to an 11w uvb cfl over a 1000w hps. They pray so hard to it that they turn each individual finger. This can get weird with multiple bulbs spaced apart. I'm not saying grow bent, just turned like individual solar panels. They also seem to mimic ca or ph issues and cause bending in the fingers, this is more subtle over time from too much exposure. If you set them up just watch for any changes, particularly with their praying(phototropism). I think it's worth you putting them in. That said, I'm not sure how noticeable it will be with cfls. Cfls already produce some uv. Definitely think anyone using only hps will notice the difference, but with other technologies already producing some uvb, I'm not sure. Nobody really knows where the cutoff point for benefits would be or if there is one. I have only maybe almost 3 years experience with using supplemental uvb but those are my thoughts from it.
