by Amber

Serious LED Grow Lighting

For years Phillips Lighting has been working with indoor urban farms and greenhouses to perfect their grow lighting – be it total lighting inside a warehouse, or light assistance in the winter greenhouse. They’ve learned what you can and cannot do under LED grow lights, and that with the right light recipe you can make fruit, vegetable, and flowering plants perform certain desirable tasks. Recently, the company realized that if they’re going to perfect this light recipe thing it will have to be done in a lab setting. Playing with light on a bound-for-market crop can only be taken so far, and with more and more city farms operating without any sunlight at all, the need for efficient grow lighting that develops the best quality produce is huge.

Enter the GrowWise City Farming research center at Royal Phillips in the Netherlands where they’re totally focused on perfecting LED light recipes to make greens, fruits, and vegetables produced indoors better.

The color of sunlight influences plants to do so many things. By studying what activities go on in different areas of the spectrum lighting technologists can create the right environment to pronounce this behavior in a controlled growing situation. If more and more people will be getting their nutrition from indoor city farms, it’s high time the leaders in grow lighting figure out how to make it not just healthier eating, but better tasting too.

Now all the indoor gardeners out there mistakenly led to believe that you can grow anything efficiently under LED lights should take note. The only growers that Phillips uses solely LED lighting are those whose crop is greens… lettuces, spinach, herbs, and the like. There is a strawberry grower under glass in Belguim that also uses only LED lighting, but they have the sun too, and strawberries are an early season crop perfectly adapted to cooler sunlight than mid to late season harvests. The LEDs help weak winter sunshine out to bring the Flemish better winter berries. For commercial food growing you need to be very serious about your grow lighting. The harvest must be high quality, and the lights are a huge part of making that happen.

So, exactly what is Phillips working to accomplish with these light recipes? They’ve discovered that certain colors of light make tomatoes juicier, and higher in vitamin C than those grown using standard light arrays and HID lights. That they can make a single type of lettuce buttery and mild, or more crunchy and a bit bitter simply by changing the diode colors in the LED array. That one color mix perfects herb flavor, while another coaxes winter berries to develop more perfect fruit than others… And that’s just a few examples that they’ve disclosed that will improve a consumer’s experience with food.

Then there are attributes that will make indoor farming more sustainable and efficient, like reducing water use. Yes, the grow lights you choose and where they are positioned can make the plants in the indoor garden require more water than another might. It can also make them more susceptible to problems like pests. Surprising, but if you give a little thought to what weak light due to cloud cover, or during times that sun becomes overly intense can do in an outdoor garden, it makes perfect sense.

It explains why it is better to mix high intensity lights with LEDs for the best crop from fruiting plants like tomatoes and peppers versus trying to accomplish the same results using nothing but HID or LED alone. You can’t light the lower portions of large plants with HIDs – it’s too hot. But you can with LEDs because they are more like filtered sunlight, burning cooler and emitting less intense light. The reason that LEDs are awesome for leafy crops is that they are more like the less intensive spring and early summer sun.

Now that they’re totally focused on tailoring these light recipes to the photosynthesis response of the plants in a lab situation Phillips will be able to get more serious about perfecting how and why we use LEDs in food production. Their new CityFarming research center allows them to tweak spectrums and experiment with light placement to find the sweet spot for all crops. We’re one step closer to dramatically increased yields, and better fruit flavor, density, and quality in indoor urban farming.

Leave a Comment

Your email address will not be published. Required fields are marked *

  • Jessica Stewart says:

    Thanks to Amber for a nice topics. Now, could you please suggest me that, How many hours to keep lighting on plants in indoor place? If you give me your valuable answer then I will be benefited for my indoor planting.

    • Serena Sayers says:

      Hi Jessica,
      The amount of hours really depends on what you’re growing, the stage it’s in (seedling, veg or bloom) and the type of lights you use. Check out our “Grow Lights” category for more information. https://gcmag.co/Grow-Lights
      I hope this helps!

    • Jessica Stewart says:

      Thanks Serena Sayers for your valuable suggestion.


The garden played a starring role from spring through fall in the house Amber was raised in. She has decades of experience growing plants from seeds and cuttings in the plot and pots.