2018 ASHS Annual Conference

Trends toward local foods are an important aspect of community health and influence factors ranging from human nutrition to economic and environmental sustainability. In response to these movements, new businesses of growing and supplying fresh and nutritious vegetables year-round for local consumption can well be established in any community or region. This study was carried out to evaluate different systems for hydroponic production of leafy greens as well as selection of suitable cultivars. Over 60 different commercial lettuce cultivars were grown in the nutrient film techniques (NFT) as well as hydroponic tub cultures. Cultivars were evaluated for their fresh biomass yield, nutritional quality, growth rate, tendency for bolting, and developing such physiological disorders as leaf margin burns. In general, the hydroponic tub culture allowed faster growth than the NFT system for most cultivars. The tub culture in which seedling plants are anchored on Styrofoam boards and floated on nutrient solution inside tubs (9 plants/tub) is a convenient way of growing healthy plants for small-scale production. Proper balancing of nutrient ions according to the analysis of local water supply is important for optimum plant growth. Temperature and humidity control is essential for the prevention of physiological disorders. Use of artificial lights like LED and LEP may be needed for winter production. Planning and scheduling of leafy green production according to market demand are important. Cultural recommendations for growing lettuce as well as other leafy green vegetables will be discussed.