As you learned back in science class, plants have this great ability to make their own food. During photosynthesis, chlorophyll converts carbon dioxide into food sugar by utilizing light energy. When these elements exist, the only thing limiting the effects of photosynthesis are the duration, color and intensity of the light that the plant receives.

In regards to hid lighting, high pressure sodium and metal halide lights provide the most photosynthetically active spectrums. More specifically, it is the “cool blue” metal halide and “warm orange” high pressure sodium colors that enhance chlorophyll activity. In the summer months when the sun is at its highest point in the sky, it is that cool light that keeps plants’ growth compact and shapely. When we get into the fall season and the sun is lower in the sky, warm light is produced which triggers fruits and flowers. The idea is to replicate the different phases of light that a plant will experience, but in a controlled environment.

Choosing the right HID Growing Lights

Based on what you now know about cool and warm light, you are equipped to select the right type of lighting for your indoor gardening project. For example, if you intend to grow green leafy vegetables or herbs, you probably want to go with a metal halide lighting system. What’s that you say, you’d like to grow some flowering plants…than high pressure sodium is the way to go! Can’t make up your mind? Nowadays, there are conversion bulbs which enable you to just buy one system, and use either type of light. This gives you the ability to start out with a metal halide bulb to get that nice compact growth, and finish off with a high pressure sodium lamp in the flowering stage to get a higher yield.