Grow Light Bulbs
The most important element of your grow lighting system would be the light bulb itself. There are different kinds of bulbs for different situations. You can get a spot grow bulb, a standard fluorescent tube, high output fluorescent tubes, compact fluorescent plant grow systems, and many others.
Choosing Grow Light Bulbs
A spot grow light
bulb is used to direct and concentrate light on a specific and small area. If you have a rare flower that you want to keep healthy, or you've just started to lay out new seeds, a spot grow bulb will be perfect to keep your seedlings and rare flowers healthy and growing well. If you are planting vegetables or plants that are less than 12 inches in height, you can use a standard fluorescent tube.
Plants that are less than 24 inches high, such as leafy vegetables, bonsai trees, orchids, and other plants will do well using a high output fluorescent tube because they give out twice the amount of light a standard fluorescent does. They also fit easily into tight spaces. Compact high intensity lights are very bright; they can be used for any kind of plant, even plants that are over 24 inches, like tomatoes and peppers.
There are other grow light bulbs such as metal halide bulbs, high pressure sodium grow bulbs and MH/HPS conversion bulbs. You should never burn them in fixtures that were not designed for them, and always make sure they have the same wattage as their fixtures. These kinds of light bulbs give out very strong light, show the true color of plants, and generally keep plants very healthy.