Answer: Indeterminate tomatoes need support, and a fence will suit them just fine providing you tie them up as they grow. If it's a solid fence in direct sunshine, there may be too much reflected heat for plants to survive during the hot summer months but if the fence is open, like chain link, the tomatoes should grow well. If your planters are about 12 inches wide and 18 inches deep they should provide enough space for the roots to develop without overcrowding. You might want to place a stake in each planter to help support the stem of the plant so it doesn't get pulled over by the weight of the fruit. Be sure to keep your containerized plants watered well - once a day may be necessary during the summer months.
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