Multichannel LED in Horticulture: necessity or nice-to-have for optimal growth?

Introduction: The Constant Evolution of LED in Horticulture

The horticultural sector is constantly challenged to cultivate more efficiently, sustainably, and productively. Grow light plays a crucial role in this, and LED technology has truly revolutionized the way we illuminate crops. Unlike traditional High Pressure Sodium lamps (HPS), LEDs offer unprecedented control over the light spectrum, which can significantly impact plant growth, development, and quality.

The rapid development of LED drivers—from simple 1-channel systems to advanced 2-, 3-, 4- (or even more) channel systems—has created a complex selection process for growers. What used to be a clear trade-off between cost and functionality has now become more fluid due to increasing possibilities. Is the latest technology always the best investment? This article delves into the practical implications of these developments. We analyze the functionality of various channel systems and help growers find the right balance between technological advancements, operational needs, and business considerations.

The Evolution of LED grow lights: from basic to advanced

The journey of LED grow lights is a fascinating story of innovation and optimization, driven by a deeper understanding of plant physiology:

– The basics: 1-channel systems (Fixed spectrum). Initially, LED grow light systems were often based on a single, fixed spectrum. This means that all built-in LEDs (blue, red, and possibly green and far-red) are controlled by a single channel. The intensity can often be dimmed, but the ratio between the colors remains constant. The primary goal is to efficiently deliver photosynthetically active light (PAR).

– The evolution: 2-channel systems (Red/Blue/Green + Switchable Far-Red). It quickly became clear that being able to switch certain colors separately offered significant advantages. The introduction of a second channel allows a basic group of colors (such as red, blue, and possibly green/white) to be combined on a single channel, while switchable far-red light is placed on a separate, switchable channel. This allows growers to more precisely control the plant’s response to far-red—essential for stretching, flowering induction, and germination—by simply switching it on or off.

– The next level: 3-channel systems (Red/Blue + Switchable Green/White + Dimmable Far Red with boost-function). With the advent of 3-channel systems, control was further refined. Here, we often see a channel for red and blue, a separate channel for switchable green/white light, and a third channel for dimmable far red. This allows growers to switch the green component on or off as needed (for example, for visual inspection or energy saving), while the dimmability of the far red allows for gradual control of plant development. A built-in boost function allows the energy from green/white and far-red (when not in use) to be directed towards blue and red, resulting in a higher output of growth light and better efficacy  This level of control has now become widely accepted as the standard for modern cultivation systems in high-tech horticulture.

– The latest generation: 4-channel systems (all colors individually switchable and dimmable). The latest development are the 4-channel systems, which offer unprecedented control. Red, green/white, blue, and far-red can each be switched and dimmed individually. This technology is becoming increasingly accessible, but it also raises a question: is the extra functionality always necessary? Because more functionality often also comes with more complexity and possibly additional investments in your climate computer, sensors and related matters. We will discuss this in more detail in a future article. If that’s not something you really need, you will not gain a profit that justifies the investment. A 1-channel solution could then even be the better option for your specific needs.

Multi-channel LED: More Possibilities, More Value?

The biggest advantage of multi-channel systems is the ability to dynamically adjust the light spectrum. This allows growers to create light recipes specifically tailored to the needs of a crop at different growth stages, or to influence specific plant characteristics.

While 3-channel NXTLED systems controlled red and blue along with far-red, and switched green/white on and off, a 4-channel system offers greater flexibility and precision. The key difference is that each channel—red, blue, green/white, and far-red—can now be dimmed and controlled independently. This gives the grower unprecedented control over the composition of the light spectrum.

This precise control opens the door to specific influences on:

– Plant elongation: More far-red light can lead to longer stems, which is desirable in some crops.

– Leaf development and biomass: Specific ratios of blue light, among other things, can influence leaf size and total plant mass.

– Flowering induction: Far-red light plays a key role in initiating flowering in many plants.

– Photosynthesis efficiency: Synergistic effects between red and far-red light can enhance photosynthesis.

Another major advantage is increased energy efficiency. For example, by switching off blue light when not needed, significant energy savings can be achieved without compromising the desired growth results.

With 4-channel systems increasingly approaching 3-channel systems in terms of accessibility, choosing the most advanced option seems logical. However, just like a car that can travel 200 km/h in a country with a 100 km/h speed limit, the question is whether you’ll actually utilize the extra capacity and whether it’s a profitable investment for your specific crop. The added functionality of a 4-channel system only delivers added value if it can be deployed strategically to achieve specific goals.

In Practice: When is 4-channel really necessary?

The decision between 3-, 4- (or more) multichannel LED depends on your specific cultivation and ambitions. Here are scenarios where the fine-grained control of a 4-channel system can truly make a significant difference:

–Research and Development (R&D): For growers, research institutions, or breeding companies experimenting with new crops, cultivation methods, or optimizing specific plant traits, 4-channel offers ultimate flexibility. It allows them to study and quantify the precise impact of different light recipes.

–Highly specific crops: Some crops, such as certain ornamental plants, medicinal plants, or crops for specific ingredients, require extremely precise control of the growth process. Here, the exact dosage of far-red and the relative proportions of all the colors can be crucial for determining the shape, color, flavor, or concentration of active compounds.

– Advanced optimization: For growers who have already reached a very high level of efficiency and are looking for the last few percent optimization in yield, quality or energy consumption, 4- (or more) multichannel can be the tool to achieve this fine tuning. A connection with a spectrum meter, photosynthesis sensor and/or energy platform makes dynamic lighting increasingly a reality.

–Future-proof and experimental: If you intend to experiment with new crops or light recipes in the future, 4- or more channel offers you the most robust and flexible basis.

It’s crucial to emphasize that effectively utilizing 4-channel systems usually requires a lot of time and attention and an in-depth knowledge of plant physiology and light recipes. Without this knowledge, a large portion of the functionality remains unused, and you may not realize the expected added value. For many common crops, a well-tuned 1-, 2- or 3-channel system can still be the most efficient and economically sound choice, especially if the primary goals are consistency, high yield, and a fast payback period without extreme specifications.

Conclusion and Strategic Considerations for Growers

The increased accessibility of 4-channel LED systems is a significant development that makes them attractive. However, the decisive factor in your investment decision should be the added value for your specific crop or your energy bill.

Before you invest, ask yourself the following strategic questions:

– What are my primary cultivation goals? Am I looking for maximum biomass, specific plant morphology, high quality, or optimization of nutrients?

– How important is fine-tuning the spectrum for my crop? Are my crops so specific that precise control over the far-red spectrum and the individual color channels is essential for my goals?

– Do I have the knowledge and resources to optimally utilize the additional functionality of a 4-channel system? Are you willing to invest time and money in the necessary plant physiology knowledge and experiment with light recipes?

– What is the expected return on investment period for the different options? Which option offers the best balance between initial investment, operational costs, and potential additional revenue or quality improvement?

Choosing between 1-, 2-, 3-, 4- (or even more) channel LED systems is a strategic decision. We’re happy to advise you, as we look beyond the technical specifications and help you analyze your growing needs and recommend the optimal lighting solution for your unique situation.

Contact us for a personal consultation about the optimal LED solution for your cultivation.