Why LEDs have a key role in the horticulture revolution
Lux, July 11, 2016
Since the discovery was made that the spectrum of light offered to plants can change plant properties (for example, blossom and fruit growth rates), there has been an enormous increase in the interest shown by the horticultural industry in LEDs. This is where LED lighting has become a crucial technology for the viability of sustainable urban farming.
Green plants predominantly use blue light (around 430 to 490 nm) and red light (around 640 to 780 nm) for photosynthesis and producing energy, but also have other absorption bands such as around 730 nm in infrared range. This range controls plant growth, among other things. The right mix and the temporary addition of certain wavelengths – adapted specifically to the individual needs of the plant – can then trigger the desired effect in line with the yield, quality, control, speed, cost and material efficiency goals of the grower. LEDs are particularly well suited to this application, down to a defined colour spectrum and flexible control.
[mks_pullquote align=”left” width=”300″ size=”20″ bg_color=”#dd9933″ txt_color=”#ffffff”]For optimum plant growth, the light must offer these aforementioned wavelength ranges, and avoid having an overall white appearance, as we may be used to seeing from LEDs.[/mks_pullquote]Incorporating an LED system that cover the optimum wavelength range means that lighting can be adapted to suit any type of plant or flower. Varying the number of LEDs providing a light source to achieve different ratios is possible without needing to amend the printed circuit board or the design of the luminaires.
The OSLON SSL portfolio from Osram Opto Semiconductors is a 1W class LED that offers a prefocused 80, a standard 120 or a wide 150 radiation pattern, avoiding the need to purchase additional lenses. A highly targeted spectra ensures that chlorophyll absorption and photosynethesis in plants is increased. It also covers wavelengths from 450nm to 660nm for deep blue to hyper red, and 730nm for far red light (critical for the flowering of many plants).
Today, LED lighting can stimulate plant growth by up to 40 per cent. Durable and long lasting LEDs are also a much more environmentally friendly alternative to standard horticultural lighting. They can significantly stimulate plant growth while drastically reducing energy consumption through the use of targeted lighting at 450, 660 and 730 nanometres. LEDs provide a strong option for lighting for all types of plants and flowers, enabling the grower to adapt the light exactly to the needs of various crops.