Home gardeners are able to grow nutritious produce in their own back yard, and tomatoes are one of the most popular crop. Just like any other plant, tomato plants need to be trimmed regularly in order to ensure proper growth and development of the plant and the fruit it bears.
Determinate tomato plants were genetically created to develop in the same way. All determinate tomatoes of a specific variety will grow to the same height, with the same number of leaves and stems. Determinate tomato plants give fruit for only a short while during the growing season, then die. They do not need to be trimmed.
Indeterminate tomato plants grow in a more free and natural way, sending out stems and leaves arbitrarily. Indeterminate tomato plants need to be trimmed because they have not been genetically engineered to grow and look a certain way.
Fungal infections are common in plants that have leaf growth on or near the soil line. Prevent infections by trimming off the stems that have leaves touching the soil.
Suckers are small plant growths that grow at the "V" where two stems meet. Although these look like stems, they are secondary "main stems" that want to grow into a separate plant attached to the main plant. This might sound like a chance to double your tomato yield, but it's actually detrimental to your plant and yield. As the name implies, the sucker will suck nutrients and energy from the primary plant. According to EdibleContainerGardening.com, if suckers are allowed to grow, they will negatively affect the health of the plant as well as the size and number of tomatoes it bears.
All thin and weak or sickly stems should be removed on a regular basis. Weak stems usually occur because bigger, fuller stems above them shield them from the sunlight. The sickly stems should be removed because they tax the plant's energy.
Trimming tomato plants should be done either by hand or with a razor blade. If you remove the stems and suckers by hand, use a pinching method with your thumb and forefinger. Use a razor blade on stems that are too thick and tough to pinch off. According to FineGardening.com, the use of scissors or clippers can cause damage to a plant because the resulting wound is too difficult to heal.