Tomatoes can be planted in one of many different arrangements that provide adequate space for plant growth. Often the spacing is based on the type of trellising and equipment that will be used in the field. The within-row and between-row spacing’s are selected to meet these limitations. The optimal plant population per acre may also be influenced by plant growth habit (compact, spreading), plant size at maturity (small, medium, large), vigour of specific cultivars, climate, soil moisture, nutrient availability, management system and soil productivity.
Generally, for production of determinate varieties on plastic mulch, a minimum of 5 feet between rows is used with an in-row spacing of 18 to 24 inches. Six feet between rows is also a popular interval. To space plants 22 inches apart in rows that are 5 feet apart requires 4,760 plants per acre. With 6-foot centers and 18 inches between plants, 4,840 plants are required per acre. Usually a single row of tomatoes is planted down the center of each plastic mulched bed.
On bare ground, space rows 48 to 72 inches apart with 18 inches to 24 inches between plants in the row. For indeterminate types of tomatoes, which produce larger plants, adjust spacing to decrease the population accordingly.