How Does Green Light Affect Plant Photosynthesis?

According to the Museum of Science and Industry, red, green, and blue make up the light you see on a TV. These three lights, including green light, affect plant photosynthesis.

Green LED grow lights for plants also may play a role in helping you provide richer crops. Greenlight photosynthesis may not produce the effect you might think it would have, however.

The Green Light Effect on Photosynthesis

First, you should understand photosynthesis. Then, it’s important to understand the connection between green light and photosynthesis.

What is plant photosynthesis?

Plant photosynthesis is the process of absorbing sunlight to create energy. Plants use this energy to make food.

The green color of plants comes from the chloroplasts that absorb sunlight. Plants also reflect some green light while taking in the red and blue light waves. There’s more to this connection between green light and photosynthesis though.

The Connection Between Green Light and Photosynthesis

Of course, you need to pay attention to myths about green lights – and grow lights in general. For instance, you might assume that just because plants are green, that you should always use green light. That’s not always the case, but it does help to have a green light.

The true connection between green light and photosynthesis is this: It confirms that your plants are producing the energy they need. The pigment of your leaves will make it obvious if you have a healthy crop or not.

Does green light for plants cause photosynthesis?

According to Michigan State University, green light is “the least efficient wavelength in the visible spectrum” for photosynthesis. That doesn’t mean you can’t use green grow light for creating photosynthesis though.

How do green grow lights affect plant growth?

When doing your own research, you might notice some reports about green grow lights that seem to contradict one another. That’s because we still have more to explore concerning the green light effect on plant growth.

For now, most scientists seem to agree that red and blue light provides the most efficient growing experience. However, a concentration of 30% green coming from a light source can benefit plants as much as blue or red waves.

Specifically, green plant lights can increase biomass, an important factor in energy production via photosynthesis. There are also signs of the upper leaves absorbing the red and blue lights and sending green light to the lower leaves.

What are some benefits of Green LED grow lights?

Again, the concept of green light photosynthesis still requires more study. However, evidence shows some benefits of green grow lights already.

Sinks deeper into leaves

One group of researchers has studied how green light can penetrate deeper into leaves than some other light waves. This may occur easier in some plants than others though, such as in sunflowers.

It may require some fine-tuning of a strong white light (which includes green waves) you plan to use, however. Otherwise, you may have to make sure the green light you use is concentrated enough to saturate your plants.

Easier on human eyes

If you ever looked directly at a white LED grow light, you know that it’s quite bright. Green light for plants reduces eye strain even more than some red or blue lights. This will benefit you if you intend to grow crops in a confined space indoors and can’t separate your growing area from the rest of your place.

Could produce a “fuller” plant

This proposed benefit may require more proof, but some sources indicate green light can make a plant fuller. They also might grow longer stems, which you don’t necessarily need except for the possibility of more buds, flowers, and leaves that later will produce more consumable crops.

Helps detect abnormalities

Some growers use green lights to detect bugs, diseases, or other plant intrusions. This is related to lowered eye strain and the ability to inspect plants more thoroughly without blinding your eyes. Different abnormal substances and conditions may visibly show up under a different light wave too.

Can provide night (moon) light

You may not have realized this, but plants have a nighttime cycle. They thrive on moonlight just as much as they do sunlight. The timing of when you plant your crops also matters, but you could use green light to mimic that process when growing indoors.

How do you use green grow lights for plants?

Green grow lights may benefit humans more than the plant itself. It’s just easier to work around a lower light frequency than red or blue, which could hurt your eyes more. Of course, white light with all the waves together puts the most strain on your eyes.

But now, how do you use the green grow lights for plants? This step-by-step guide can get you started.

1. Find a place for your plants.

Consult your plant growing guides to ensure you give them enough room to mature. You usually need at least 6-12 inches around smaller plants to accommodate leaf spread.

If you want to produce multiple growing columns, make sure the shelf above the lower plants provides room as plants get taller. By the way, place your crops by the windows to take advantage of natural sunlight when possible too. This will reduce your indoor energy bill.

2. Get the right grow lamp.

If you’re starting out and unsure if you want to use green LED light all the time, pick a lamp that emits multiple colors. Then, you can switch it to the color you want to use and test it out without investing so much of your resources up front as a beginning indoor plant grower.

It also would do you well to pick a programmable grow lamp. This will benefit you, so you don’t have to remember to adjust the light colors and intensity all the time.

3. Pick a bright enough bulb (not too bright though!)

Most LED and fluorescent lights shine brighter than your average incandescent household light. You need that extra brightness to home in on some of that energy that normally comes from the sun.

Of course, you’re not going to ever use or find a light as bright as the sun. That could cause a fire anyway, and you want to stay safe indoors.

Experts recommend about 20-25 watts or about 500 lumens of fluorescent or LED light per square foot. Don’t go too bright, or you could strain your eyes and burn your plant leaves. This figure, however, represents using full-spectrum white light and depends on the type of harvest you intend to produce.

You may do well with at least 1,000 lumens if using green light waves. Having a grow lamp that allows for switching light colors when you need to can help you adjust to the appropriate brightness.

4. Set a timer (if your grow light has one)

If you have a grow lamp that has a timer, set it. Otherwise, set an alarm on your phone or another device. This will remind you to change the grow light colors and intensities when you need to.

Having lights switch on and off automatically while still making sure you check on your plants would benefit you the most. It keeps learning how to grow plants indoors simple as you continue to take pride in your crops.

5. Observe your plants.

You may not grasp the concept of growing immediately upon producing your first seedlings. Be patient with yourself and keep an eye on your plants. Continue to experiment with the green LED lights and see if they will produce the green light photosynthesis action you hoped for.

6. Maintain your crops as usual.

Of course, you still must cultivate your soil and water the plants. Doing this correctly will probably matter more than the type of light you use. Consult the gardening guides you usually use for knowing what soil, how much water and sunlight you need, and so on.

When possible, you also should grow your indoor crop near windows. Think of the green plant light as an important supplement to the maintenance process, not a replacement for sunlight.

7. Enjoy the harvest!

Of course, there’s no shame in reaping the benefits of any plants you have grown with green light. Enjoy your harvest once they’ve reached maturity and have given you a consumable crop.