Skill is 80% of the grow so yes almost anything "will work"; you can grow a plant with home depot grow bulbs. Doesn't mean you should..
You "should" if that's what you can afford and that's what's available to you. Specialized grow equipment is better, but not if you can't get or afford it!
Anyway, the poster started with the premise that he's using CFLs. I agree 100% those aren't the best for anything but very small grows, but since that's what he was asking about, that's how I answered.
Normal CFL will work, heck you can grow with baseball stadium lights; it's a similar idea to using Walmart grow lights. Your light is the fuel, if you buy nothing else for your grow put your money in lights. T5, HPS and MH only; please please please don't use normal HID.
Well, to be clear HID ("high intensity discharge") can refer to both metal halide and high pressure sodium lamps. The same light used to light your parking lot or warehouse can be used to grow plants, its just not quite optimized for that particular application. I agree that the biggest "bang for buck" investment is in lamp cost. But these are pretty cheap nowadays. You can buy a 250W magnetic ballast AND reflector AND bulb kit for under $150 now. If you've got the space, for a relatively modest cost, something like that will totally blow away any jury-rigged CFL system.
The T5 is the only one able to emit the correct light spectrum needed for proper growth.
With due respect, have you ever tried growing using CFLs or T8 bulbs? I've grown with all of these (MH, HPS, HO-T5s, T8s, CFLs, not to mention sun) and though they all have their own individual plusses and minuses, all of them can work.
In fact, going way back to the 1970s, before T5s or CFLs even existed, people have been growing indoors using standard T12 fluorescent bulbs. Hell, DJ short bred his famous "blueberry" strain under conventional fluorescent lights, IIRC.
Sure, there are some people who use specialized frequency/bulb lighting, but in fact most people who grow with T5s use the standard 2700K/3000K and/or 6400K bulbs. There is no "magic" to those bulbs; CFL bulbs are commonly available in the exact same spectra. Again, the main advantage of t5s is just that they're straight and easily reflectable to use the full output of the light. CFLs simply aren't designed to be used in that way.
Again, it comes down to what you're trying to do, what your budget is, and what your physical space limitations are.
My "bottom line" when it comes to CFLs is that they're fine for seedlings, vegging small plants, or taking maybe 1-2 SMALL plants through flower, but that's it. IMO, if you need more than 150W of CFL, you're really better off with HID lighting, or possibly T5/LED instead.
