Tomato plants are floppy by nature. Left to sprawl, the plants are more disease-prone and fruit quality suffers. Choose a trellising system that lifts the plants off the ground and allows for air circulation.
Install wood or rebar stakes, at least 6 feet tall, at planting time. As the plants grow, tie the stems loosely to the stakes with twine or strips of fabric.
Fashion three stakes into a basic tripod for extra stability in windy regions; train a tomato plant on the upwind stake. Fancy tuteurs made of wood, bamboo, or bent twigs are the classier choice for ornamental kitchen gardens.
Cylindrical or square wire cages keep tomatoes upright without the need for tying the stems. Commercial versions tend to be small and flimsy, but homemade cages fashioned from livestock panels are strong and durable.