Concrete reinforcing wire, generally considered to be the best, is available in rolls of varying lengths. A 5-foot length makes a tomato cage 18 to 20 inches in diameter. Cages are held together by bending and crimping the wire ends around one of the vertical wires. To keep the cage supported and standing, snip off the bottom ring of the cage and push the remaining prongs into the ground. Install cages around young transplants and anchor all sides well with wire stakes in the soil.
Adequate anchorage is essential for cages covered with plastic or spunweb during windy periods.
Covered transplants will be protected from virus-carrying thrips and aphids until the plant touches the sides of the cage and plastic has to be removed. Plants covered with spunweb never have to be uncovered. Plastic covering must be removed when foliage begins to touch the edges and bunch against the sides of plastic. This will usually be about the time the plant has marble-sized fruit. Because of excessive heat build-up, the plastic covering must be removed when temperatures regularly begin to reach the high 80s.