Urban agriculture is developping fast because more and more people live in urban areas. Moreover urban food production is local, cheaper and social. There is therefore a need for advanced indoor techniques to cultivate plants. Indoor techniques will also benefits people leaving in far northern and southern latitudes due to long yearly periods with no or little sunlight. As plants prefer some light colours, using specific colours might improve plant growth. Sabzalian et al. tested red, blue and white light-emitting diode (LED) to grow mint, lentil, basil, and four ornamental plants. Their experiments unraveled surprising performance and production of vegetables and ornamental plants.