There are three different types of “traditional” lights that people use to grow plants.
High-pressure sodium lights
Fluorescent lights
Metal halide lights
Today, advances in technology have brought LED lights into the grow light competitive arena. However, it’s the LED lights specifically that some greenhouse owners feel aren’t living up to the publicity surrounding them.
For those growing fruit and flowers, these types of lights are the most popular by far. High-pressure sodium lights produce intense, bright light that contains most of the oranges and reds within the color spectrum.
A downside is that they also get incredibly hot. If you use these kinds of grow lights, you’ll need to ensure that your greenhouse is well ventilated and that you manage the overall temperature inside.
If you’re working with plants that need lower light levels or are starting seedlings, then fluorescent lights are a perfect choice. Typically inexpensive, you can usually find these types of lights in many stores. Also, they’re easier to use than any of the other grow lights on this list.
Be that as it may, these kind of grow lights aren’t that great as primary light sources. Used as secondary lighting, however, fluorescent lights can be pretty effective.