Tomato plants are warm-season annuals that are grown over most of the continental United States. For a jump start on your plants, sow them indoors six weeks before the average last frost in your area. If planted outside when the night temperature is still below 55 degrees F, there won't be much growth on your plants. Tomatoes come in two varieties---bush and upright. The bush varieties don't need much trimming, but the upright varieties do or they'll put all their energy into making leaves.
Amend your garden soil by adding small amounts of washed dairy compost. Till in with your rototiller.
Dig a hole in the soil and plant your tomato plant. Don't worry about planting it too deep. Roots will form along the stem if planted too deeply. These will actually make the plant sturdier and help ensure survival.
Water the soil and mulch with straw or hay to retain moisture. Apply 1 inch of water per week around your tomato plant when rainfall is lacking.
Prune away yellowing leaves and also stems that touch the ground. Prune off side stems that grow between the leaf and main stems. You'll notice these growing after your plants begin setting fruit.
Break off the growing point of each stem once your tomato plant has six or seven trusses. Depending on where you live, this pruning will take place between July and September. This will allow your plant to concentrate on producing and ripening fruit rather than growing more leaves.