Why is Red Light Good for Plants? : Indoor Plants Growth!

If you’re growing indoor plants/ greenhouse plants, you better be concerned about light effects. 

Well, the outdoor plants receive all these red and blue lights naturally. You’ll need a lower percentage of blue light and a higher percentage of red light for healthy indoor plants.

However, Red-lights have some specific responsibility behind your indoor plant’s growth and production. Especially when your plants reach the maturity level, you must need an adequate amount of red lights. 

If you’re new in this greenhouse plantation world, you might wonder why red light is suitable for plants? No worries, we got your back. You must learn more about red light efficiency for a healthy indoor garden in your house.

Why is Red Light Good for Plants

Check this too: COB VS SMD LED For Growing Indoor Plants

How does Red Light Intensity Affect Your Plants? 

Red light intensity plays a vital role in your plant growth. There are hundreds of benefits your plant can’t get because of the absence of sunlight.

For outdoor plants, they get a blanched light intensity naturally. But indoor plants can’t absorb all the natural elements from nature. That’s why you need to attach extra light to provide better intensity.

During the flowering days of plants, they need some extra strength. And red light intensity helps them to provide all the natural components to proceed with their photosynthesis system. Even red lights make your plants stronger and absorb more energy. 

Why is Red Light Good for Plants?

The indoor plantation is not less than understanding science. For healthy growth, you’ve to provide all the elements and ingredients that outdoor plants get.

Give a quick check and learn why red lights seem so good for your plants:

Photosynthesis System

Plants will require both red and blue lights for their photosynthesis system. They will make produce their energy through these lights. Red lights stimulate the photosynthesis system on an instantaneous basis.

Moreover, red lights fit with chlorophylls and produce sugars and carbons for your plant’s photosynthesis system. 

Plant’s physiology

Red lights symbolize the radiation that plants receive while the sun is low. This symbolization deals with the plant’s physiology.

The plant might realize it’s the winter/ rainy season, morning or evening time of the day. As the plants will think they are in the shade, it won’t harm their natural growth. 

Extension growth

There has a lot of plants that must require red lights for their growth. These red lights help your plant to be stronger, healthier and taller.

Under daylights, your plant leaves grow thin and large. Plants that grow in red light generally have more delicate leaves and tall heights.

A balanced combination of red lights and minimum blue lights ensures better extension growth of your indoor plants.  

Flower and Fruit production

Red lights control the flower phytochrome reversibility system. It is required for your plant fruit and flower production. Red lights trigger the plant hormones and give it better growth.

Plant pigments will absorb red lights and help you to get better speed and root development. Especially for the grown-up plants, this light gets more critical.

As that is their growth time, you can not expect adequate flowers and fruit production without this light.

Efficient brightness

Ideally, plants require four different colors of lights for adequate growth. These are red, blue, green and yellow.

Among all, red light is more important and plays a vital role in plant growth. Red lights seem more dimmed compared to other colors of lights.

It gets more accessible for the plants to absorb more lights. 

Experts suggest adding 80% red lights in the greenhouse to keep up the uninterrupted photosynthesis system. If you’re using green and yellow lights, still keep the red ratio at least 50%.

Check this too: What Plants Don’t Like Epsom Salt?


Why do plants absorb red light the best?

It might be consuming that why do pants absorb red lights better. There has also three more colors that help plants to get greener and grow stronger. Plants seem to absorb red light the most.

Even if you’re using four different colors in a greenhouse garden, you have to ensure that the plants get at least a 50% red light supply.

Besides their need, there have a few more reasons.

  • Red lights seem to convert electricity into photosynthesis easily and quickly.
  • As it is more effective in the photosynthesis system, chlorophyll absorbs it better. 
  • Plant phytochromes have both active and inactive forms to absorb red lights.
  • Red lights are more dimmed and less bright. So, they don’t reflect into our eyes. 
  • The phytochrome sensitivity of the flower promotes flowering.

Regarding all these facts and growing nature, plants absorb the red lights better.

Is only red light enough for your plants? 

Yes, plants that grow up in only red lights won’t get the other elements balanced for their photosynthesis system.

Red lights might help them in the blooming, flowering or producing time. In the early life of the plants, they stay more sensitive. Then, they will need blue lights, and for greener leaves, green lights are also important. Using only red lights can’t grow them big, healthy and robust at the same time. 

Plants are meant to absorb different colors from sunlight. For the healthier growth of your indoor plants, provide the same balanced ratio of lights. 

What are the best colors of lights for plants?

Indoor plants will require all colors of lights that outdoor plants get naturally. However, red and blue lights seem the most important for plants from the seeding to production time.

Can you use 2 in one blue and red LED lights to grow plants?

Yes, 2 in one LED lights that can change their color seem handier. You might not have to change the bulbs again and again. You can go for red and blue 2 in LED lights for your indoor plants. 


Different colored LED lights play vital roles in healthy plantations. However, red lights seem more absorbing and helpful for expected growth and production. Red LED lights are easy to get and affordable as well. Hopefully, now you know why red light is good for plants. Try to set a balanced ratio of lights for indoor plants and get healthier production.

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