increasing its market value; and improved the health of the livestock, which decreased the perinatal mortality of the herd.4 ADVANTAGES OVER SOIL AGRICULTURE Higher Yields Than Conventional Agriculture The hydroponic system is more productive and efficient than conventional farming. Hydroponic crops have greater yields and, often, higher nutritional values than traditional agricultural crops (Christie 2014; Buchanan and Omaye 2013; Gichuhi et al. 2009; Selma et al. 2012; Sgherri et al. 2010). Hydroponic systems also require fewer pesticides (Resh and Howard 2012). The reason for the greater yields is that hydroponics allows for continuous year-round production and shorter harvest cycles than soil-based farming methods. The exact number of annual growing seasons depends on the type of hydroponic system being used and the climatic conditions within that system. For example, outdoor system growing seasons are still dictated by the outdoor temperature and daylight hours. Plants grown hydroponically are generally less stressed than soil-grown plants since hydroponic plants are in their optimum growing conditions all the time, which creates less waste than conventional farming (Treftz and Omaye 2016). Moreover, hydroponic crops have similar, and sometimes higher, levels of vitamins and minerals compared with soil-based cultivation systems (Gruda 2009). The pilot in Kenya’s Kakuma refugee camp (box 5.1) showed that hydroponic systems require up to 75 percent less space than traditional field farming methods (WFP Kenya 2020). Reduced Water Usage Hydroponic systems use less water than open-field agriculture (Ly 2011; Despommier 2010). According to Despommier (2010), hydroponics requires approximately 80 to 99 percent less water than traditional agriculture, with the more advanced hydroponic systems using less water than simplified systems. Hydroponic and aeroponic techniques deliver the optimal amount of water needed for healthy plant growth. The same principle is true for nutrients, which producers can mix precisely and deliver to plants, thereby optimizing the growing conditions for each plant’s species, growth stage, and nutrient requirements (Wootton-Beard 2019). Hydroponic systems have been successful in water-stressed environments in Africa. Between October 2018 and March 2019, a hydroponic pilot project was carried out in Djibouti (Ministry of Agriculture of Djibouti 2019), one of Africa’s more arid countries. The project benefited 27 Djiboutians. In Kenya, Hydroponics Africa Limited provides training and installations of hydroponic, aquaponic, and greenhouse structures. The company has installed more than 3,500 hydroponic units and trained more than 5,000 small-scale farmers in Rwanda, Somalia, Tanzania, and Uganda. Sixty-five percent of these units are located in dry regions. The WFP hydroponic pilot project in the Kakuma 212
Insect and Hydroponic Farming in Africa
