Growing tomatoes up rather than out is probably the most popular vertical gardening technique of all. Here are two tried and true ways.
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One tried-and-true way is use wooden stakes. With this method, use a stake that is at least 5' tall and an inch or two wide with a V on the bottom end. Place the stake 3" away from a newly planted tomato plant, then use a hammer to pound the stake about 1" deep into the soil. Attach old strips of cloth about every 10" along the stake by tying the strips tightly around the wood. As the tomato grows, loosely tie the stem to the stake. For best results, prune off all but one or two main stems.
Caged tomato fruits are usually clean and of high quality The two basic types of tomato cages found in garden stores are the round type and those that fold flat but open up into a square. Both cages are installed by pushing the wire legs into the ground around a newly planted tomato. Tomatoes that are grown inside cages rarely need to be tied. But if you wish, you can give the vines a helping hand by loosely tying the stalks to the cage with pieces of soft twine.