Tomatoes: Fresh Market and Processing - 2010 Ohio Vegetable Production Guide
Tomatoes are a warm-season crop and are one of Ohio’s most important vegetables. Ohio ranks second nationally in processing tomatoes, with about 7,000 A producing an average yield of 29 t/A and a crop farmgate value of more than $16 million. Fresh-market tomatoes are for the wholesale, retail and supermarket trade.
Most fresh-market tomatoes are produced from locally grown transplants or from southern-grown plants. The key to good transplant production is sufficient space. Adequate spacing produces a short, stocky plant with a good root system for early production. Do not transplant too early unless trying for an early market. Start and grow plants at 60°F nights for smooth fruit and early clusters. Sow seeds about 7 weeks before plants are to be set in the field. Cell sizes of 1.5-2.0 inches produce better plants than smaller cell sizes. A more popular and widely used tray size is the 96 square plug flat. Some growers are even using smaller plugs such as a 200 square plug flat. Harden plants slightly by decreasing temperature and water. Overhardening by exposure to very low temperatures and excessive starving results in plants that take off slower and produce lower yields. Set plants no more than 1 inch deeper than in the flats. Otherwise, roots do not grow and vegetative growth is retarded, while new roots develop on the stem. Ground tomatoes on plastic and “San Diego” stringtype trellis systems are the most common training methods. Tomatoes for the supermarket trade, the semi determinate types, are well suited for ground culture. Disease control is difficult during wet, humid periods and is one disadvantage to ground culture. String trellis systems provide more air circulation, but there is more danger of sunscald on the fruit. Trellis tomatoes produce earlier fruit when pruned to one or two stems, in comparison with ground culture systems.
Select well-drained soils or provide surface and subsurface drainage systems. A 3-year rotation is preferred, with a crop other than corn planted the previous growing season. Avoid fields with residual nitrogen and where triazine herbicides may present a carryover problem. Locally grown or southern transplants are used for field establishment. Use only certified plants from southern states. Transplants give earlier maturity than direct seeding, and nearly all processing tomato acreage in the Great Lakes region is established using transplants. Twin-row plantings with small bush-type varieties are now more common and can increase yields by 25%. Field planting starts in late April and continues until June 15. The advantages of direct seeding are lower cost per acre; reduced chances for disease introduction; and flexibility in planting time, variety selection and plant population. It is important to prepare plant beds for direct seeding or transplants as early as possible, regardless of soil type. Well-formed beds help surface drainage whether the beds are made in late fall or early spring. Fall bed making is preferred with clay loams and some silt loams. Beds generally are spaced 60 inches between centers (66 inches for some harvesters). Bed shape is determined by harvesting equipment.