Vertical farming is booming, and above all in an urban context, since this method requires less space in order to grow sufficient food for a large number of people. Vertical farming is an agricultural concept where crops are grown in a tall greenhouse, in vertically stacked layers. The plants are not planted in earth; instead, they are cultivated in nutrient-enriched water. Artificial light is needed to ensure that the plants receive enough light in order to grow. But which sort of light gives the best result? This is the focus of one of the studies by a team of bio-engineers from Ghent University.