Effects of Two Planting Densities on Leafy and Fruiting Crops in Aquaponic Hoophouse Production

Aquaponics, the practice of growing fish and plants in the same system, has become increasingly popular as a solution to food scarcity, especially in urban areas. However, most current research is focused on fish rearing or growth of plants. Our research focused on planting density for two leafy plants, kale ( Brassica oleracea L.) and cilantro ( Coriandrum sativum L.), and two fruiting plants, banana peppers ( Capsicum annuum L.) and pole beans ( Phaseolus vulgaris L.), at high (30, 37, 12, and 14 plants/m 2 ) and low (20, 26, 6, and 7 plants/m 2 ) planting densities, respectively. Six aquaponic systems were set up in a hoophouse in Stillwater, OK, USA, and stocked with bluegill ( Lepomis macrochirus L.) fingerlings. All crops were found to have a greater vegetative biomass at lower planting densities, as well as greater chlorophyll content in all plants except banana peppers. Number and weight of fruit did not change significantly between planting densities, but peppers were longer at greater densities.