Thanks for writing. To get maximum yield from your tomatoes, make sure they're growing in a spot that has full sun (at least 6 to 8 hours of direct sun each day) and they're growing in moist soil. Don't let them dry out and don't let the ground stay soggy for extended periods.
Select disease-resistant varieties --- if your plants become infected by any of the wilts or blights that commonly attack tomatoes, they'll produce less fruit.
Some research has also shown that mulching the ground around your tomatoes with red plastic can increase yields.
Feed the tomatoes a general-purpose plant food regularly. Many gardeners prefer organic fertilizers because they feed the tomatoes over a longer period of time and improve the soil as they feed the plant.
Also be sure to give your tomatoes good support --- such as from a trellis, tomato cage, or other device that keeps the plants growing upright and spread out so air can freely flow through all the leaves.
---Justin, Senior Garden Editor, BHG.com"