Yeah they will work. I am not saying you will get massive yields but they will prob be about ample for the job. Remember the more light the better. Would go for maybe four of them though, as with only 1 you may struggle, and try and position them within an inch of the foliage. There is loads of good stuff on here about the pros and cons of using Cfls. I have used them myself with not bad results. Best of luck.