Choosing the Appropriate Grow Light
In hydroponic gardens, natural sunlight is replaced by specialized “grow lights” which are especially made to emit the spectrum that the plant needs most. The type of grow light you need, of course, depends on several factors, such as the kind of plant and the plant behavior that you are trying to encourage.
First, it’s important to have a background about color temperature so as to fully comprehend the concept of grow lights. In the subject of plant lighting, “temperature” refers to color, and not heat. The color spectrum is measured in degrees Kelvin, in the same way as some applications of heat and cold are except higher temperatures are considered “cooler”, and lower ones are “warmer.” The temperatures that highly resemble that of natural sunlight are those ranging over 5000K, and is seen as blue on the color spectrum. Interestingly, the reds, oranges and yellows are lower temperature, within the range 2700K and below. Note that leafy vegetation does better in the 6000K range (essentially full sunlight) while flowering as well as fruiting plants need the temperature to be around 4800K – those considered in the cooler blue zone. Plants are also drawing more from the orange-red color temperatures, which are around 2700K, when they are flowering and reproducing. So you can understand why the right grow light setting can be so important.
The 3 most common kinds of grow light used in hydroponic growing rooms are designed toward the color temperatures most needed by plant life. The Metal Halide bulb is among the most popular. If you like a grow light that resembles natural sunlight the closest, then you should go for High-Intensity Discharge (HID) bulb, Metal Halide bulbs. As previously mentioned, this type of grow light is great for leafy plants. The High Pressure Sodium bulb (also another HID bulb) is your second alternative. These bulbs produce the orange-red part of the spectrum (approximately 2200K) and are good for flowering, but don’t encourage full foliage. They’re not generally used by themselves, but in combination with other bulbs and/or natural light. The 3rd most common bulb is the fluorescent either high-output or low-output. Even if they’re not as intense as the HID bulbs, they remain useful particularly due to the fact that since they emit so little heat, they can be placed close to the plants.
Today, LED bulbs have been designed, some of which claim to take care of the full range of color temperature for plant life with almost no heat. The only major fallback is, they’re usually very expensive – and many less costly bulbs are available that can do the job just as perfectly.
To conclude, many hydroponic gardens today use a combination of different bulbs for the various stages of plant growth. Your retailer shall be able to advise you on what grow light combination will be perfect for you.
