HID – High Intensity Diode Lighting
High Intensity Diode lights are the main lights used by growers. This is because they produce the most useable light for plants and therefore produce the highest yield/m2 and fastest growth rates. They have also been around for a long time so growers are comfortable with them.
HID Grow Lights come in two different varieties of bulb: HPS and MH. Most growers who use HID lighting will use HPS and MH bulbs in their grow room and change the type of bulb depending on the stage their plants are at in the growth cycle.While HID lights have a number of benefits, they do have some draw-backs. They are big electricity users and will cost more to run than LED of CFL lights. Also, they create a lot of heat so it is important to have good ventilation and extraction systems in place. HID bulbs also degrade over time and should be replaced every 3-5 grows. Because HID lights are so powerful, a separate lighting ballast is required to power the bulbs.
CFL – Compact Fluorescent Lighting
For indoor and hydroponic gardening, CFL lights are another commonly used lighting technology. CFL bulbs are less powerful than the other lighting technologies available. They also cost less and produce less heat which makes them a good choice for getting your plants started, sprouting seed, and growing clones. They are also a good choice for growers who have a very small space to grow in or who want to grow a small amount without investing too much in equipment.
CFL bulbs come in a range of types, namely the spiral CFLs (which look like a much larger CFL light for your home), and T5 fluorescent tube lighting, which are long straight tubes.
Being cheaper and putting out very little heat does have its drawbacks. Mature plants will have much slower growth rates under CFLs than the other two lighting technologies. For this reason professional indoor and hydroponic growers will use CFLs only for baby plants and clones. However, for hobby growers looking to grow a modest amount on a small budget, CFL lights may very well be the best choice.
LED – Light Emitting Diode Grow Lights
The third option is greenhouse grow lights. These share some of the advantages of both HID lights as well as CFLs, however they have some of their own draw backs as well.
Until recently, LED horticultural lighting technology hadn’t progressed far enough to be a good option. This didn’t stop numerous suppliers for selling “LED Grow Lights” that underperformed and led to disappointing yields for growers. However, LED technology has now progressed to a point where cob led grow light is a viable choice for your indoor garden or hydroponic setup.
LED lights are more efficient than HIDs in terms of their ability to turn electricity into usable light for your plants. This means that they produce less heat and use less electricity than comparable HID setups. This is gentler on your power bill and makes temperature control easier. The downside is that powerful led grow light will generally produce less yield per m2 than a comparable HID. They are however much more powerful than CFL lighting setups. Further, high-quality LED grow lights are more expensive to buy than their comparable HID equivalents. Beware lower-priced full spectrum light as they will provide very poor performance and disappointing yields/results.
LED Lighting Pros: More powerful and effective than CFLs. Much less heat output than HIDs. Lower energy use/running costs.

LED Lighting Cons: Less yield than comparable HIDs (regardless of what anyone says – don’t believe the hype!) Expensive purchase price will scare off some growers.