(6) Sucker Removal and Pruning Affect on Heirloom Tomato Yield and Fruit Size

Abstract

Heirloom tomato production is increasing in the Eastern United states as consumer demand increases. Pruning and suckering heirloom tomatoes have not been studied to see if there is any need for this labor-intensive activity. A 2-year study was undertaken to evaluate whether pruning or suckering would affect yield or fruit size for two heirloom cultivars (`Mortgage Lifter' and `Prudens Purple'). The treatments imposed on the cultivars were 1) removing all suckers from the second or third stem down after the flower cluster; 2) removing the bottom two suckers, or 3) removing no suckers. Pruning had no effect on early yield or fruit size (harvests 1–4). Mid-season (harvests 5–7) total and marketable yields were significantly higher for removing two suckers or not suckering over the other two treatments for year 1, but not year 2. The tomato fruit size was only reduced for the non-suckering treatment. There were no statistical differences among the pruning treatments for yield or fruit size for late season harvests (8-10) for both years. Marketable yields were statistically higher for no suckering over the two- and three-stem treatments, but not different from two suckers when all harvests were combined for the season for year 1. No statistical differences were observed in year 2. However, fruit size was reduced when not suckering compared to the other treatments. The cultivar `Prudens Purple' did have higher total and marketable yield than `Mortgage Lifter' for both early and total combined harvests, but not for mid- or late-season harvests in year 1. There were no statistical differences between the two cultivars for year 2.