2018 ASHS Annual Conference

Bell pepper selections suited specifically well for intense management in greenhouse environments are now available. For optimal crop management and use of space, these peppers are usually trellised in vertical growing systems. A practice of one to four primary stems with pruned side shoots is often used to encourage reproductive growth and enhance productivity. Some cultivars have a tendency to produce a large number of fruits followed by periods of limited pepper development. To balance the fruit load over the season, selective removal of flowers has been suggested. The greenhouse bell pepper cultivars Felicitas (red), Sympathy (orange), and Bentley (yellow) were included to evaluate reducing the flower number for more consistent fruit development and harvest. Seeds were sown on Feb. 8 and the study conducted from Mar. 17 through Sept. 11. The plants were grown in a high-wire drip irrigation system using dutch (bato) buckets (17.7 L volume) filled with a 50/50 mixture of perlite and a peatlite medium (Pro-Mix BX). The plants were trellised using two primary shoots off the main stem in a “V” shaped system. The lateral side-stems developing on the two primary stems were trimmed over three leaves throughout the study. In treatments with flower removal, every third flower was removed to allow no more than two sequential nodes on a stem to develop fruits. The pepper fruits were harvested mature with at least 90 percent color formation. Plants with no flower removal produced slightly higher yields over the 16 weeks of harvest. The total yield per plant was 4.2 ± 0.99 kg for Felicitas, 3.7 ± 0.51 kg for Sympathy and 4.1 ± 0.75 kg for Bentley. Although there were small variations in overall yield, the size of individual peppers was not affected by the flower management. Subsequently, additional pepper fruits developed for harvest on intact plants. The number of harvested peppers per plant averaged 20 ± 3.7 (Felicitas), 18 ± 2.8 (Sympathy), and 17 ± 2.3 (Bentley). Flower removal reduced the number of harvested fruits on a plant with 2 for Bentley or 3 for Felicitas and Symphony. The average weight of individual fruits was 217 ± 18.7 grams for Felicitas, 199 ± 13.8 for Sympathy and 242 ± 11.6 grams for Bentley. Removing flowers to balance the fruit load over the season resulted in less variation in individual fruit size and more uniform pepper development and harvest.