Plant seedlings grown by LEDs prove higher quality than those grown using sodium lamps and sunlight

Researchers from Purdue University have successfully grown ornamental plant seedlings indoors, exclusively with red and blue LEDs, according to a greenhouse study published in the journal HortScience. The research discovered that replacing the sodium arcs with LEDs yielded the same, and in some cases, better results than the saplings grown using high-pressure sodium lamps to supplement the little sunlight available in the winter and early spring, when the saplings are typically grown. When LED lighting was used as the sole source of lighting, the end result was further improved, resulting in a uniform, compact, and sturdy sapling. 

Associate professor Roberto Lopez used a technique called multilayer production to grow the ornamental plant seedlings, a technique in which the pockets of soil are layered on top of each other and grown in an enclosed area where climate is regulated using ceiling fans and controlled-air systems. The major benefit associated with this kind of environment is that no outside factors such as temperature and humidity fluctuations ever affect growth. 

In the final leg of the research, Lopez and doctoral student Joshua Carver, are experimenting with various LED configurations and colors — red, blue, white, and far-red LEDs— to accelerate seedling growth beyond the average 3-4 week duration. The goal is to help the plants bloom faster by shaving a week off production. 

Source: PHYS.org