With more edible crops being produced in protected growing environments, lights can be tailored to increase produce growth and crop flowering. Blue LEDs are important for vegetative growth while red LEDs drive fruiting and flowering.
Philips Lighting showcased its GreenPower Dynamic LED production module at GreenTech this summer. It aims to provide "horticultural lighting and software that allows growers and researchers the ability to adjust dynamically both the LED colours in the spectrum".
The company believes LED growth recipes can influence the length, weight, vase life, flower colour and uniformity of a cut flower, alongside the ability to improve taste and vitamin C levels in test strawberries, by using LED growth recipes. LEDs' narrow spectral bands optimise chlorophyll absorption in plants, driving photosynthesis. Research continues on light wavelengths, specifically RB (red and blue), and how to further boost productivity in protected growing situations.
Recent LED research by Professor Chungui Lu at Nottingham Trent University targeted the increasing food-growing facilities using protected environments and supplementary lighting. "Light is one of the most important environmental factors affecting plant growth," he said. "We have found that RB LEDs are more effective than white light in facilitating biomass growth in lettuce, helping growers produce larger plants. Our research has also found that artificial light may hold health benefits. Lettuce grown under our research LEDs holds reduced excess nitrates."
LEDs and growing indoors allow growers to minimise the distance between the farm and consumers. Lu added: "Yield loss happens during harvest, transport and shelf life. Minimising the transport time and distance cuts yield loss and extends shelf life." Lighting controls, dimmers and sensors are all being incorporated in systems to create more sophisticated growing environments and make energy savings.
Philips Lighting Horticulture LED Solutions business leader Udo van Slooten said: "The GreenPower Dynamic LED lighting system is the latest innovation in the range. Now growers and researchers can grow a variety of crops with dynamic LED lighting spectra and intensities with just one LED system. This means they can work with dynamic light recipes to meet the different growth needs of specific crops, flowers and plants."
The system can also help with energy savings, "reducing electricity consumption compared to the previous high-pressure sodium lighting systems, while simultaneously enhancing crop taste and yield, which is a win-win situation".
A team at the Massachusetts Institute of Technology has created a new incandescent light bulb to compete with LEDs that they believe is more efficient. Using a special crystal structure surrounding the filament, they "bounce back the energy that would usually be lost as heat while allowing the light through".
- Philips GrowWise has revealed the results of its research on light-enabled city farming on the first anniversary of the project. The LED manufacturer said spicier mustard, more fragrant basil and fresher lettuce grown without daylight are among the results from 50 research projects carried out at its GrowWise Center.
The facility at the High Tech Campus in Eindhoven, the Netherlands, aims to develop the blueprint for the vertical farm of the future. The research findings confirm that growth recipes can be successfully used to influence virtually any crop characteristic.