Optimizing Plant Density and Production Systems to Maximize Yield of Greenhouse-grown ‘Trust’ Tomatoes

Abstract

Plant spacing and production systems are important factors for maximizing production of greenhouse-grown tomatoes (Solanum lycopersicum). Two studies were conducted simultaneously and independently, each in a 33 × 96-ft greenhouse in Fall 2008 and Spring 2009 using perlite soilless bag culture. The purpose of the first study was to evaluate yield and fruit weight of ‘Trust’ tomatoes spaced 12, 16, 20, 24, or 28 inches in-row. The second study was conducted to determine the effect of pruning production systems on yield and fruit weight. The first system is pruning two plants per bag each to a single leader and the second is pruning one plant per bag to double leader. A plant spacing of 28 inches resulted in significantly more fruit per plant than the 12-inch plant spacing. However, yield per area decreased with wider plant spacings. Plants spaced 12 inches apart in-row produced 2.8 and 3.8 lb/ft2 total yield in the fall and spring, respectively, compared with plants spaced 28 inches apart that produced 1.7 and 2.2 lb/ft2 in the fall and spring. Using a production system with one plant per bag pruned to a double leader increased yield by 6.4 lb/plant in the fall and 15.7 lb/plant in the spring. On a per bag basis, pruning two tomato plants to one leader increased total yield by 2.6 lb/bag and was more economical in the fall; whereas, in the spring, the double leader production system did not affect yield but was more economical.