Record-breaking tomato growing is an obsession with some farmers and there is a reason why. Tomato growing is simple. Several varieties of tomato plants grow large with little extra care. The 'Big Zac' hybrid grows 4 to 6 lb. tomatoes without extreme amounts of care. To get the really big tomatoes however, there are some simple tricks and training methods, along with standard growing techniques, which encourage the plant to grow the largest tomatoes possible.
Test the pH of your soil and ensure the pH is between 6.5 and 7.0. This is the optimum growing condition for the plant. For soil that is above a reading of 7.0 and is considered alkaline and requires an application of sulfur, while soil under 7 is considered acidic and requires the addition of lime. Apply lime or sulfur at 1 pound per 1000 square feet of gardening area.
Plant your tomato plant early in the season giving it plenty of room away from other tomato plants (at least 32 inches) and cover it with a glass cloche. This provides a greenhouse effect for the tomato plants, protecting them from cold weather and disease in the cool spring.
Mulch the plant once it begins to flower to retain moisture in the soil.
Let one stem of the tomato plant develop and remove sucker vines from the plant. These appear between the branches and the main stem. Support the main stem with a stake, tying it to the stake with a pair of pantyhose.
Fertilize the soil with a fish emulsion fertilizer every two weeks to give the tomato plant a quick burst of nutrients.
Remove all fruit except for one or two so that they get the best nutrients. Leave the fruit that is closest to the vine and remove those that stick out from the plant.
Water regularly and hope for the largest tomatoes ever.