Previously, for optimized plant growth, indoor growers were fond of using full-spectrum lights, which are designed to mimic natural sunlight. Cultivators believed that such lighting options were more robust than conventional units, capable of facilitating the food-making process in a reliable manner. Advancements in LED lights technology have provided other, potentially more effective lighting methods for indoor farmers. Instead of leveraging full-spectrum luminaries, individuals incorporate red and blue LED chips to initiate an ideal response from the plants.
LEDs and Photosynthesis
Red light, with a wavelength measurement of 625 – 740 nm, and blue light, with a wavelength measurement of 435 – 500 nm, actively interact with plants and promote photosynthesis. Chlorophyll components inside plants are more prone to absorbing red light bands, compared to other colors. As a mainstream color option, it is cost-effective to use red LED lights inside grow rooms.
On the other hand, blue light affects plant growth during the flowering stages. Compared to red light, less concentrations of blue are needed for large yields. Only a small amount is required to regulate the functions of the stomata, which is related to the plant’s ability to take in carbon dioxide and manage water levels.
Compared to full-spectrum grow lights, using red and blue LED fixtures for indoor cultivation can result in increased growth rates, up to 20 percent (according to Purdue University).
Reducing Heat Generation
Red and blue LED chips for indoor cultivation can help decrease the negative effects of heat generation during growth. The solid-state units consume very little energy during operation, resulting in cool illumination. This feature allows farmers to consolidate more chips in a lighting system for dense configurations over the plot.
From a distance, greenhouses that incorporate red and blue LED grow lights appear pink or purple (depending on the ratio of colors). Some lighting systems may include hints of green light, which generally have the same benefits as blue-colored variants.