Rob - there are several applications for
fluorescent plant lighting and some very good plant spectrum tubes that work well.
Some uses include seedling/root propagation and growing "low energy" requirement plants. These include some herbs, salad
greens, etc. Fluorescent
lights cannot be used for high energy plants; ie: Any blossoming, fruit producing plant. Incandescent
"spot-grow"
bulbs put out more energy (lumens) but cost more to operate.
When considering "cheap lights" consider this: A standard 100 Watt incandescent spot grow light puts out about 1260 lumens;
a 100 Watt High Intensity Discharge (H.I.D) light puts out about 9000 lumens. With H.I.D. lights you are getting 8 times the
output than standard incandescent lights using the same power!
Also, H.I.D. lights put out better color for plant growth than any of the other choices at better light penetration. So, in my
opinion, even with the initial cost (and there are good deals out there!) H.I.D. lighting is really the best choice for indoor plant
growth.