If you’ve ever walked past the biology building on the Texas Tech campus at night, then you have probably seen the greenhouse that glows a bright purple color. Why is this?
Well, Vikram Baliga, a research associate, greenhouse manager, and self-proclaimed ‘plant nerd’ at Texas Tech University, recently posted a video to TikTok explaining how light impacts plant growth.
According to the video Baliga posted, plants, like the cucumber plants they have growing in the greenhouse, primarily absorb red and blue light. So, when putting lights in a greenhouse, they have to consider what will provide the best type of light to help the plants grow. This means matching the lights to the red and blue spectrums that the plants absorb the best.
The type of light that the plant needs to grow best can vary depending on things like the time of year. For example, if you want to simulate the light plants get in the summer, it will be more red than blue.
So, knowing that plants need blue and red light to grow the best explains the color of the lights in the greenhouse. If you mix red and blue, you get what looks like purple.
Baliga also talks about the reason that most plants look green to us. This is because most plants don't absorb green light, therefore reflecting the green light into our eyes, giving them that color.
This may be information that you will never need in your day-to-day life, but at least now you know why the greenhouse at Tech glows purple at night.