Pruning tomato plants is an elective approach that some gardeners use to produce earlier harvests, higher yields, and healthier plants. This option is practiced on indeterminate tomato varieties, which produce new young leaves and flowers perpetually through the growing season.
If left unpruned, tomatoes can grow into unruly, tangled plants that can monopolize your garden, bend, break and outgrow its space. Pinching away the new growth of tomato sucker stems can tame your tomato plants, and improve the plant’s health, vigor, and production of fruit.
Indeterminate vs. Determinate plants
If you have never heard of indeterminate or determinate varieties of tomato plants, you are not alone. Many gardeners grow plenty of tomatoes successfully without pruning or knowing the difference between the two.
- Determinate tomatoes tend to be more of a bush tomato variety. They are more compact and only reach a height of three to four feet and stop growing when fruits develop on the top bud. The determinate forms stop their shoot production once flowers form on the ends.
- Indeterminate tomato varieties will form flowers along the sides of the shoots and continue to grow and produce tomatoes until their first frost kills them. This type of tomato can attain heights between six to twelve of up to 12 feet and can greatly benefit from pruning of its tomato suckers.
What is a tomato sucker?
Tomato suckers are small stalks that tomato plants develop in the space between the stem and a leaf branch called the axil. They grow on both types of tomatoes: determinate plants (bush) and indeterminate plants (vining).
Traditionally, gardeners prune tomato suckers off indeterminate tomato plants because they continue to produce leaves throughout the entirety of the growing season. Tomato sucker growths pull energy from the plant to grow its stalks and leaves, rather than using its energy to blossom and produce fruit.
Benefits of Pruning Tomato Plants
Properly pruning your tomato plants improves their shape and eliminates conditions that can promote the growth of fungus and disease. Unpruned tomato plants tend to form numerous vines that follow the ground, producing dense growth that can prevent leaves from drying efficiently.
The removal of extraneous leaves and offshoots provides more airflow through your plants. Better air circulation means that leaves will dry more efficiently, diminishing the breeding ground for fungus growth and other diseases that can destroy your tomato plants. When tomato plants get pruned regularly, its leaves receive sufficient sunlight, and the plant can photosynthesize more efficiently, boosting growth and fruit production.
Naturally, the better that you can see the fruits on your plants, the more ease you will have with identifying and picking the ripened fruit. A properly pruned plant also allows you easier access to the plant, eliminating shoot and stem breakage during harvesting.
By having less foliage to contend with, the plant will be able to put more energy toward growing larger fruit. Sometimes, you might discover very large clusters of tomatoes in one area of the plant, which can seem very exciting. However, the fruit from these clusters will probably not grow as large as they are capable of growing without some intervention. Try to harvest the ripest tomatoes from those clusters to give the others a chance to reach their growth potential.
The regular pruning of your tomato plants can result in earlier ripening on the vine. Pruned plants will have more energy left-over to work on ripening the existing fruit on the plant instead of dispersing its energy to growing new fruits.
Steps for Pruning Tomato Plants
Prune indeterminate tomato plants throughout the growing season. You can use these garden season milestones as your guide. For best results, remove suckers while they’re young so that they can be pinched-off cleanly and easily. Prune tomato plants early in the morning when the weather is dry. This practice allows the stems to recover best to resist disease.
Prune at Planting Time
Pinch off the lower leaves of the tomato plant and bury a good section of the stem deep in the soil. Additional roots will form from the stem and increase the growth potential for your tomato plants. Clear away any bud flowers that are on your plant even if they were present when you purchased the plant. You want the growing energy to surge into the leaves of the plant at this early phase of growth.
Continue to remove flowers from the tomato plants until they are 12 to 18 inches tall. This practice continues to ensure that the roots of the plant are receiving the maximum direct energy.
Snip or pinch off all leafy tomato suckers that have grown beneath the first cluster of tomatoes. Pinching tomato suckers off when they are young helps to minimize the damage to the plant’s main stem tissue.
Toward the close of the growing season, you likely have a ton of un-ripened fruit on the vines. To fully benefit from this ripened fruit before the tomato plant succumbs to the season-ending elements, remove the excess leaf growth and any branches that do not have fruit formed on them. This important step adds necessary stress to the plant. It directs the plant to focus its energy on ripening what is already there, rather than expending energy to produce more fruit that will never have time to reach its full ripeness before season’s end. If you are a gardener who prefers maintaining some green tomatoes for frying, you can skip this step and harvest away.