Leafy Greens LED grow lights

Maximize leafy greens production
with Sollum Technologies’ LED grow light

Leafy green vegetables are a staple of a healthy diet because of their nutritional content, namely vitamins, minerals and fiber. Indoor cultivation has risen in recent years with more and more varieties of produce available to consumers. With frequent unpredictable weather occurring more often as the Earth’s temperature rises, growers can turn to indoor planting to ensure predictable harvests to maintain a healthy business.  

If lettuce is a well-known staple of indoor planting, the possibilities for crops are endless with spinach, kale, arugula, microgreens and herbs such as the popular basil. Thanks to greenhouse growers, locally-produced leafy green vegetables can be delivered fresh to consumers all year-round. 

Higher yield with LED grow lights for leafy greens

The flexibility of dynamic LED grow lights is definitely a plus in increasing crop yield. The short cycle of leafy greens such as lettuce means that growers need to apply the right light treatment from the get-go. When successful, growers can increase the number of crops annually, which translates into additional revenue.  

For example, red-leafed varieties benefit from a different lighting strategy than green-leafed varieties, with a growth-centered recipe during the production stage (e.g., Days 7-21) driving photosynthesis and biomass growth. This recipe may be followed by a high-blue treatment 3 to 5 days before harvesting to enhance the red color (and nutritional value, as a bonus). If growers were to apply a high-blue light recipe for the duration of the crop cycle, the crop would grow more slowly and remain too compact. Tailoring the light spectrum allows growers to get the best crop in terms of quality and yield.  

In addition, growing in a greenhouse means we need to consider the natural light conditions as well, which vary throughout the year as does the temperature and humidity. In these fluctuating conditions, the benefits of an adaptive lighting system truly shine.  

Grower’s experience considerable daily fluctuations in natural light levels during the shoulder months of the year (October-November and March-April). These fluctuations occur day to day but also within a day. In this context, a traditional non-dynamic LED lighting system provides growers with limited tools to respond to real-time light levels, which then exposes crops to inconsistent lighting which can cause plant stress and that affect yield (and quality).  

Dynamic LED grow lights such as Sollum’s enable an infinite number of micro adjustments in spectrum, intensity (ePPFD) and photoperiod from a PC or a smartphone in real time. Simply put, our solution allows growers to be ready for anything. Sollum’s SUN as a Service® (SUNaaS®) cloud platform enables real-time compensation which dims the output of the light fixtures incrementally according to the ambient light conditions ― growers do not need to intervene. This ensures that crops receive uniform light levels, contributing to predictable growth patterns and higher yield. With unstable weather patterns cause by climate change, predictable harvests in greenhouses become a very attractive option. 

Higher quality leafy greens with dynamic LED grow lights

While uniform light levels are ideal for crop consistency and reducing plant stress, spectral tuning with dynamic lighting allows growers to control plant morphology to meet consumer preferences for quality. By adjusting the light spectrum (also known as color or light quality), growers can achieve the desired leaf size and thickness and leaf color. This is true for any leafy green produce. 

For example, with baby leaf lettuce, growers need to grow a snackable product, highlighting the importance of crispness, leaf thickness, and a strong stem for consumers to snack on the product as easily between their fingers or fork. 

Another example is boosting the output of far-red light to reach the right leaf length. And all of these spectral modifications can be done within seconds, meaning it is just as easy to flip the far-red on for leaf extension as it is to shut it off to keep the leaves crisp during the final days of production.  

A major challenge for lettuce production is the management of tipburn, to which lighting contributes by altering plant activity and altering the balance between light and temperature. With HPS lighting, tipburn can be induced when the lights shut off due to a rapid drop in temperature. With fixed LED lighting, tipburn can be caused when they are turned on due to increased plant activity but a slower temperature increase.  

With dynamic lighting, applying sunrise and sunset sequences allow the grower to gradually impact plant activity at the beginning and end of the day, avoiding tipburn. However, lighting is only one piece of the puzzle and temperature management must also be aligned.   

With Sollum, growers monitoring the progress of crops can adjust the lighting to achieve maximum quality rather than live with the outcomes of a non-dynamic lighting system. And this is made easy thanks to Sollum’s Smart Support team and library of recipes providing guidance at every stage of crop growth, and for every variety, 24/7.