LED Light Can Boost Green Onion Growth
Green onions, with their mild onion-like flavor, are a versatile ingredient enjoyed in many dishes and serve as a staple in cuisines around the world, particularly across East Asia.
Generally, green onions are cultivated in open fields. However, growing demand for higher yields, improved quality, and reduced reliance on pesticides has created new challenges for green onion production.
LED grow lights have already demonstrated effectiveness in promoting the growth of crops such as tomatoes, strawberries, and cucumbers in controlled environments like greenhouses and vertical farms. Building on these results, researchers and farmers are now testing LED supplementation in open-field green onion cultivation. Studies indicate that LED lighting can enhance plant growth while also decreasing pesticide requirements.
In this blog, we’ll take a closer look at how LED lighting technology can support and improve commercial green onion production.
Red LEDs Help Grow More Green Onions Under Solar Panels
Agrovoltaics, the practice of combining solar panels with crop cultivation, offers a promising way to maximize land use while producing renewable energy. The challenge, however, is that the panels inevitably cast shade, often reducing crop yield. A study explored whether supplemental red LED lighting could offset this problem for green onions, and even improve production beyond normal open-field conditions [1].
Researchers set up a demonstration field in Korea where solar panels covered about a third of the cultivation area, mounted two meters above the ground. They compared green onions grown under solar panels with and without supplemental red LED lighting, and also measured performance against onions grown in open sunlight. The LEDs, operating at 660 nm, were run for either three or six hours after sunset, ensuring light was available during critical evening hours.
The results were striking. Onions grown under panels without lighting showed the expected drop in yield compared to open-field crops. Yet when red LEDs were introduced, productivity not only recovered but surpassed the control. With three hours of supplemental light, the yield jumped nearly 39% compared to onions in full sunlight. Six hours of light also boosted growth and chlorophyll content, though the benefits plateaued compared to the shorter lighting period. Importantly, the additional energy consumption of the LEDs amounted to less than one percent of the electricity produced by the solar panels themselves, making the system highly efficient.
Therefore, for farmers considering solar panels, it’s exciting news that at least three hours of red LED lighting after sunset can strike the balance between energy use and yield gains, opening a path for more sustainable and profitable farming systems.
Green LED Lighting Enhances Green Onion Cultivation
In Taiwan, the integration of green LED lighting has significantly improved green onion farming. This innovative approach has led to a 40% reduction in beet armyworm infestations and a 20% increase in green onion yields. The green LED light disrupts the beet armyworm's reproductive cycle, effectively reducing pest populations without the need for chemical pesticides. This method is particularly beneficial as the larvae often hide within the tubular leaves of the onions, making traditional pesticide application less effective. Additionally, the green LED lighting promotes healthier plant growth, contributing to higher yields and improved crop quality.
This advancement underscores the potential of LED technology in sustainable agriculture, offering a dual benefit of pest control and enhanced crop production.
Blue and White LED Lights Enhance Green Onion Growth and Nutrition
A 2022 study published in Scientia Horticulturae explored how different combinations of LED light spectra affect the growth and nutritional content of green onions.
The researchers found that a combination of blue and white LED lights significantly improved both growth and nutrient accumulation in green onions. This lighting combination promoted better nutrient accumulation and enhanced antioxidant capacity in the plants. Interestingly, the study also observed that green LED light can penetrate deeper into the plant canopy, potentially aiding in more uniform growth and healthier leaves.
These findings suggest that selecting the right LED light spectrum can be a powerful tool for green onion production and enhance crop yield and nutritional value. By tailoring light conditions to the specific needs of the plants, farmers can optimize growth and produce healthier, more robust green onions.
Looking for customized horticulture lighting solutions? Contact Atop Lighting, your trusted partner for successful cultivation.
Reference
- Kim, H., Lee, S., & Kang, J. (2023). Growth and agronomic traits of green onion under the agrovoltaic system with red supplemental LED lighting. Journal of People, Plants, and Environment, 26(1), 1–12. https://doi.org/10.11628/ksppe.2023.26.1.1
- Gao, S., et al. (2022). Effect of different LED light quality combinations on the growth and nutrient accumulation in green onion (Allium fistulosum L.). Scientia Horticulturae, 302, 111143. https://doi.org/10.1016/j.scienta.2022.111143
