The Benefits of Using Blue LED Lighting at the End of Production Cycles

Published: September 26, 2016

While indoor farming offers distinct benefits when compared to outdoor agricultural production, certain plants do not develop sufficient pigments to provide the plants the colors consumers expect. New research finds using red-blue LED lighting at the end of the production cycle overcomes this obstacle.  

4.1

Recent research demonstrates of using blue LED lights at the end of the production cycle for lettuce.

 

Even economists who monitor agricultural markets now recognize the advantages of greenhouse and indoor hydroponic crop production. Many of these benefits stem from the ability to control growing conditions, such as the quality, quantity, and duration of light exposure, temperature, carbon dioxide and relative humidity levels, and the amount of water and nutrients provided to the plants. Until recently, greenhouse growers who relied on ambient sunlight for illumination faced a significant challenge – the glazing on the glass and the structure of their grow facilities blocked as much as 50 percent of photosynthetic producing light. As a result, certain types of produce, such as red leaf lettuce, do not develop pigments that give the vegetables the characteristic color consumers expect. Fortunately, horticulturalists working at Purdue University recently published their research findings that provide a solution – exposing plants to blue and red LED lights at the end of the production cycle spurs the synthesis of the pigments that give plants the color consumers demand.

 

The Benefits of LED Lighting as a Sole Source of Illumination

 

The scientists based their research on previous studies demonstrating the advantages of using red-blue LED grow lights as the sole lighting source in indoor farming environments. Some examples of the benefits include the following:

 

  • Plants contain higher levels of chlorophyll, which allows the plants to capture more energy for photosynthesis
  • The plants grown using LED lighting produced more phenols, flavonoids, and antioxidants than those grown using other light sources.
  • Plants produced using LED grow lights have better leaf structure and greater size when compared to plants grown using other types of illumination.

 

What effects did using different spectrums of LED lighting at the end of the production cycle have on plants?

 

Exposure to LED Lighting Improves Plant Color

 

The research team at Purdue compared the levels of the pigment anthocyanin, which gives plants a reddish hue, in red leaf lettuce grown with different end of production lighting sources. The five different lighting conditions included the following:

 

  • A control condition with no supplemental lighting at the end of the production cycle.
  • High-Pressure Sodium (HPS) lighting used as a supplemental lighting source applied at the end of the growth cycle.
  • An experimental group using only monochromatic red LED grow lights at the end of production
  • An experimental group using only monochromatic blue LED lighting
  • A group of plants exposed to a combination of red and blue LED grow lights

 

The picture below illustrates the color differences in the red leaf lettuce varietals grown in each of the lighting conditions.

4.2

 

 

The findings of this study are as follows:

 

  • Plants exposed to LED lighting for as few as three days at the end of the production cycle had deeper red leaves than those not exposed to LED lights.
  • The maximum improvement in leaf color occurred seven days earlier in plants exposed to a 50:50 mix of red and blue LED lights throughout the growth cycle.
  • Monochromatic blue lights increased anthocyanin seven days sooner than plants in the monochromatic red condition, which emphasizes the importance of light in the blue area of the spectrum for the production of this pigment.

 

If you are considering making a switch to LED grow lights, this research demonstrates a way to make the transition incrementally if you are not in a place to equip your entire indoor grow operation at one time.

 

Do you want to know the LED light mix that is best for your crops? Our LED light experts are available for free consultations. Call or email your questions to our team today!

 

Sources:

 

N.A. (2010).  Anthocyanins. Phytochemicals.

 

N.A. (2014). The Light Fantastic. The Economist.

 

Owen, W.G. & R.G. Lopez.(2015). End-of-production Supplemental Lighting with Red and Blue Light-emitting Diodes (LEDs) Influences Red Pigmentation of Four Lettuce Varieties. Horticultural Science, 50 (5): 676-684.  

 

The Advantages of Using LED Lighting in Forest Seedling Greenhouses

Published: September 1, 2016

Advances in LED grow light technology provide greenhouse tree growers with a cost-efficient light source to produce healthier and more attractive trees when compared to other forms of illumination. Cultivating delicate sequoia seedling indoors protects them from the elements. Both the US Forestry Service and private tree nurseries face the same challenge when cultivating young… Read more »

Improve the Marketability of Hydroponically Grown Vegetables by Using LED Lights

Published: August 9, 2016

As health-conscious consumers demand nutrient dense vegetables with exceptional flavor and appearance, hydroponic growers can optimize the growth, nutrient content, and taste of their crops by using red, blue, and white LED lights.        The popularity of local farmers’ markets has led to increased demand for organically grown fresh produce. As American consumers become… Read more »

LED Lights Enhance Gerbera Blooms, Growth, and Marketability

Published: July 9, 2016

Cut flower production provides indoor growers profitable market opportunities. Research indicated LED lights are essential for maximizing yields, bloom quality, and revenue.   Gerbera daisies are in high demand in the US florist industry. If you plan to expand and diversify your indoor grow operations, consider the opportunity offered by the cut flower market. In… Read more »

The Use of LED Lighting to Cultivate Potatoes, Oilseed Rape, and Soybeans

Published: June 14, 2016

  A recent study added to the body of evidence that LED grow lights provide distinct advantages in terms of plant growth and disease resistance when compared to cultivars grown under florescent lighting.   Potatoes grown under LED lights have a higher biomass and grow more quickly than those grown using fluorescent lighting. As the… Read more »

How to Select LED Lighting for Nutraceutical Plant Production

Published: May 31, 2016

As consumers look for natural alternatives to synthetic pharmaceutical treatments, the global nutraceutical market is growing at a compound annual growth rate of 7 percent. How can LED lighting help your efforts to produce plants for this market? Antioxidant-rich organic strawberries are just one of many products sought by health conscious consumers. With rising healthcare… Read more »

Avoid Climate-Related Crop Production Disruption with LED Grow Lights

Published: May 27, 2016

If you still use traditional outdoor agricultural practices, transitioning your crops to a greenhouse or other indoor grow facility will increase your yields and help avoid the negative effects of an increasingly unpredictable climate. Transitioning to indoor grow facilities, such as hydroponic grow rooms, illuminated with LED grow light not only protect plants but also… Read more »

The Effects of Light Quantity and Quality on Plant Characteristics

Published: May 21, 2016

Choosing the right LED grow light recipe for your indoor crops is essential for ensuring robust healthy plants with the qualities most desired by consumers. LEDs that produce far-red and red light regulate the germination and blooming cycle of plants. Just like the location of a field where a farmer grows his crops affects the… Read more »

Picky Plants Thrive Under LED Lighting

Published: May 14, 2016

Scientists advise indoor growers to select narrow wavelength LED lights to ensure full-fragranced blooms and the most palate pleasing fruits and vegetables. Choosing the LED lights to maximize the flavor and aroma of your crops is dependent upon the cultivars you plant. A common frustration among those who grow flowers, fruits, herbs, and vegetables indoors… Read more »