Comparison of Two Hydroponic Tower Systems for Lettuce Production
Jacob C. Domenghini, Robert Cavasos, Cynthia M. Domenghini

Abstract
Hydroponic vegetable production is increasing at a rate of 3% each year. Vertical farming has proven to use less land and water than traditional farming. Black Seeded Simpson lettuce, Lactuca sativa, was grown to test the performance of two hydroponic towers, a commercially available tower and a student-designed tower in an indoor farming system in Richmond, KY, in 2016.Each tower contained 24plant compartments. The commercial tower compartments were evenly spaced on a 20 cm diameter, 1.2 m tall pipe; the student-designed tower compartments were dispersed on two 10 cm diameter pipes that were 1.2 m tall. An average-size leaf from each compartment was harvested weekly and leaf area index (LAI) and leaf weight were measured. Lettuce was destructively harvested at the conclusion of the studies and total LAI and leaf weight recorded for each tower. The commercial tower produced significantly higher yields (P=0.05) with an average LAI of 2092.4 cm2 and leaf weight of 66.9 g per compartment compared to the average LAI and leaf weight yields of the student tower which were 1594.2 cm2 and 52.2 g respectively. Poor light distribution to the lettuce located between the two pipes likely caused lower yields from the student tower.

Full Text: PDF     DOI: 10.15640/jaes.v11n2a1