Vertical Farming of Medicinal Plants

Medicinal plants have been used in traditional medicine, health food supplements, rituals, and for health care purposes for thousands of years. According to the Food and Agriculture Organization of the United Nations (FAO), the worldwide production of medicinal and aromatic plants is estimated to be 330 million tons for a total area of 77 million ha. Nowadays, the sector of medicinal plants is subject to inconstancy, and issues about the yield, quality, and efficacy of plant extracts have been reported. The present review describes the current status of medicinal plants worldwide, including a detailed description of the sector in France. The suitability of vertical farming for the production of medicinal plants is discussed, and its advantages and drawbacks are presented. Indoor cultivation in a controlled environment requires appropriate adjustment of abiotic factors to optimize biomass and secondary metabolite contents. Light quantity and quality, nutrient solution, temperature, and CO2 concentration are presented in relation with their impact on plants and on the production of the targeted phytocompound. A case-study on the technic feasibility and economic viability of producing a plant-based drug in a vertical container is presented, including plant cultivation and drug extraction steps. Based on the costs related directly to the production activity, it provides a rapid estimate of the direct production cost of each step. The largest contributor to cultivation costs is labor, averaging 48%, followed by energy (20%) and investment cost (20%). The largest contributor to extraction and purification costs is the operating and maintenance cost of equipment (47%), followed by energy cost (31%) and labor cost (16%). The largest contributor to the whole plant-based drug production process, from plant cultivation to drug production, is the research and development cost (98–67%), followed by cultivation and extraction costs (1–24%) and drug manufacturing costs (1–8%), depending on the number of containers, i.e., on the productivity of the cultivation and extraction steps.