You can find CFL's at hardware stores.

However, they are generally low grade, short lived and the spectrum is NOT FULL SPECTRUM.

Also, lumen output is very low.

You can grow with the CFL at the hardware store, but your veg period will double and the harvest will suffer as they don't penetrate the plant canopy as well.

But you can do it.
HARDDON Reviewed by HARDDON on . QUALITY CFL's 3 days ago I added BACK to my grow, the 5500K CFL I have. The pics below, 3 days ago had ZERO foilage on the bottom. As of now, 3 days later, massive new growth is emergin at many nodes even some thought to be lifeless. Those of you using CFL's make sure you keep the undersides lit as well. I wish I had made it work earlier. Watch for the burns and if needed, keep fans on them. Rating: 5