Trellis System, Plant Density, and Container Type Can Improve Fruit Yield and Plant Growth of a Greenhouse Hydroponic Pepper Crop

Elio Jovicich and Daniel J. Cantliffe

The production and quality of hydroponic grown red bell pepper fruits (Capsicum annuum L. cv. HA3378) were tested in a passive ventilated greenhouse during spring and summer 2000 in Gainesville, FL. Two plant growing systems were used: 1) "V" trellis system (plants pruned to two stems); and 2) "Spanish" trellis system (plants not pruned, with lateral strings and vertical poles for canopy support). Plants were grown in bags (20.4 L, 1-m long) and polyethylene pots (11.5 L) both filled with perlite. Plant population densities were 1.5, 1.9, 3.0, and 3.8 plant/m². Low night winter temperatures (4 to 15°C) during first flowering and fruit setting lead to the production of flat shaped parthenocarpic fruits in the first harvest (3/1/2000). Marketable fruit yield was similar in both growing systems (27 No·m^-2, 5.0 kg·m^-2) although production of extra large grade yield was higher in non-pruned (21 No·m^-2, 4.9 kg·m^-2) plants. Marketable yield per plant was greater in non-pruned plants than in pruned plants, and was not affected by plant population density. However, marketable yield per m2 increased linearly with plant density from 3.5 kg·m^-2 (1.5 plant/m²) to 7.4 kg·m^-2 (3.8 plant/m²). Plants in bags produced a greater number of smaller fruits than plants in pots but had the same marketable yields per m². In spring and summer, the production of fruits with blossom end-rot (BER), epidermal cracking, and spots was high. Non-pruned plants had a lower percentage of BER (39%) than pruned plants (62%). In non-pruned plants the number of nodes was greater than in pruned plants (105 vs. 59), but fruit set was lower (34% vs. 50%). Fruit set per plant decreased with plant density while plant height slightly increased. In a greenhouse with simple environmental control systems and production under high temperatures, the "Spanish" trellis system with a density of 3.8 plant/m² resulted in reduced labor requirements and in greater fruit yields and quality.