Tomatoes are an annual plant that needs to be replanted each year. Bush and compact dwarf types of tomatoes do not usually need to be supported, unless their fruit becomes too heavy. Regular tomato plants can have branches that grow 8 to 12 feet long in warm climates. Plant tomato plants 15 to 18 inches apart, with 2 to 3 feet between rows. Supporting your tomato plants encourages greater fruit production, easier harvesting and increased air circulation. Supports can reduce injury to the plant and fruit.
Set long stakes or poles in the ground close to the tomato plant. Make sure that the stake is firmly set in the dirt, and is at least 4 feet tall above the ground. Tie the main stem loosely to the pole. As the tomato plant grows, retie the stem farther up on the stake.
Tomato cages can be homemade or commercially made. The cage provides support for the tomato plant as it grows, and you do not have to tie the plant to the cage. Place the cage around a tomato plant while it is still young and small. As the plant grows, carefully arrange the tomato branches to rest on the cage supports. Make sure that the mesh of the cage is large enough to get your hand through to pick the ripe fruit.
If tomato plants are grown in a greenhouse, they can be trained up a heavy string. Tie a heavy string or rope to the strong beams in the greenhouse roof. Tie the other end to a short stake near the bottom of the plant. As the tomato plant grows, train the tomato vine to twist around the string.
Create a tepee with three or four sides, at least 4 feet tall. Run string or wire around the tepee. Plant one tomato plant on each side of the tepee. Train the tomato plants to grow up the side of the tepee. Tie them to the supports as they grow. This provides plenty of room for easy harvesting and air circulation. It also allows for an alternate garden design than tomato plants in rows.