Hydroponic lights, also referred to as grow lights, are used, sometimes in combination with one of its other varieties, to attain the best lighting results. If you are using natural sunlight in any way, the grow lights will be used to supplement natural light; if you are using solely artificial lighting, your setup would naturally be a tad more complicated.
When setting up hydroponic lighting, it is essential to have a firm grasp of the principle of color temperature and its effects on plant life. Not to be confused with heat/cold, color temperature refers to the color spectrum of light, and is measured in degrees Kelvin. Blue light - at around 6000K - is considered the coolest while red-orange light - at the 2000K range - is regarded as the warmest. The darker blue spectrum - which resembles normal sunlight the most - is good for full-vegetation plants, while the slightly warmer color temperatures are best for fruit and flowering plants. In the reproductive/flowering stage, plants draw from the red-orange part of the spectrum. In the most favorable lighting setup, your hydroponic lights shall cover a combination of these color temperatures best suited for the plants you are growing.
The most common type of bulb utilized in hydroponic lighting is the Metal Halide (MH) bulb. This High-Intensity Discharge (HID) light leans most toward the blue side of the spectrum, resembles direct sunlight the most, and is preferred for almost all growing situations. As such, this bulb works best with leafy, full-vegetation plants.
Another HID bulb used is the High Pressure Sodium (HPS) bulb. This bulb tends to emit orange-red light approximately on the 2200K mark, and is best for flowering plants, but not ideal as an artificial lighting substitute. It should generally be used in combination with natural sunlight or other artificial bulbs.
Flourescent lighting is your third alternative. These bulbs are less expensive and they emit less heat, as such, they can be placed so close to the plants.
Still, you have even more alternatives: (1) incandescent light which is not as intense and would get too warm when placed too closely to the plants and (2) LED lights, which can cover the spectrum well without emitting heat but are way too expensive.
As you can tell, there are a wide range of combinations that can be made from these hydroponic lights. The combination that is ideal for your garden can be determined with your retailer.
This article was added on Thursday 24 December, 2009.
