Light and horticulture : the LEDs era

Humanity is facing two major challenges: increasing demand for energy and food on the one hand, and climate change on the other. With the world's population on the rise, these two social challenges seem irreconcilable.

At the current rate of food demand, the production rate per hectare would have to be increased by 50% by 2050 to ensure our food security.

Among the solutions envisaged to achieve this objective, indoor cultivation, in all its forms, is set to expand to complement traditional outdoor growing methods.

Light plays a major role in plant development, and special attention must be paid to it in indoor horticulture. This article reviews the impact of the lighting environment on plant growth from a theoretical, application and technological perspective.

First, the photobiology of plants is discussed. Next, the various applications of artificial light, both in the cultivation and post-cultivation phases, are examined. In the third part, the contribution of light-emitting diodes in this field is discussed. Finally, a conclusion underlines that, thanks to the technological contribution of LEDs in this field, light has more than one trick up its sleeve and can be used in applications that go far beyond "simple" efficient crop lighting.