Greenhouse Lighting

When looking at how location affects lighting solutions, nowhere is this more evident than a greenhouse. With greenhouse lighting, there is a host of factors to consider when looking for the right application.

Since the matter of dealing with living plants changes the type of solutions which are appropriate, greenhouse lighting can sometimes be a tricky area to illuminate. However, there are a few ways to make it easier.

  • Know your plants. While this is a no-brainer for anyone in charge of a greenhouse, it still bears repeating. Some plants need more light than others to flourish while other plants may die from an abundance of light. The key is to know what the plant needs in order to survive when it comes to lighting.
  • Light by section. While again this may be common knowledge for more experienced growers, many newer greenhouse owners or hobbyists may forget this tip. Plants in need of high light levels should be grouped together while low light plants should be grouped together. This will not only ensure healthy plants, but it will cut down on the number of fixtures you will need since you are lighting by group instead of individually.
  • Understand the relationship to heat. While plants in need of high levels of sunlight for survival are typically hearty enough to handle the heat that comes along with the natural sunshine, there will also be light solutions of lower lumen output or brightness which will give off considerable heat. Whatever lighting solution you choose, you need to look at lumen and heat output together to make an informed choice.
  • Pay attention to the color temperature. Since some lights give off different colored wavelengths, such as reds or ultraviolet, you need to be aware of this factor. Some plants will experience better growth with certain wavelength colors. For example, UVB wavelengths are harmful to plants whereas anything on the spectrum from violet to green is ideal, and the red bands offer the best results in terms of flowering and growth.

There are a few types of lighting which are commonly seen in this type of environment. Again, the type of plants will determine the best solution for greenhouse lighting.

Metal Halide

This solution produces light in the blue wavelength spectrum which is great for the initial growing phase. It offers an average lifespan of around 10,000 hours which makes it great as a primary light source for a variety of plants. While they don’t last as long as other options, they offer an affordable solution for smaller greenhouses or personal indoor gardens.

High-Pressure Sodium

Falling under the orange spectrum, this type of lighting is ideal for when you need more intense coloring to aide in flowering phases of growth. This type of lighting solution has a longer lifespan than metal halide with an average of 18,000 hours, and work well in conjunction with natural light.


While this type of lamp wasn’t common in greenhouses until recently, there are a few reasons to consider using them. They offer a more energy efficient option to save on utilities, release lower heat levels, and are relativity affordable. Another thing about this option is that it offers a better color rendering index than HPS or metal halide which is good for plants.


When looking for an option with no heat for delicate plants, this is the way to go. Available in the full-color spectrum, these versatile lights produce no heat, offer the best lumen to wattage consumed ratio for better efficiency, and last longer than other solutions.