Blacklight during dark period?

Due to my climate, I have been forced to have my 12 hours on to be from 9pm to 9am and my babies sleep all day when its warm-ish. I really want to work with them during the day so can I use a blacklight to light the area without throwing them out of flowering? or will this produce the same effect?
Thanks.

If you have to use any light, it should be green.