Tomato plants naturally produce auxiliary branches known as suckers, which influence the plant’s overall health and harvest quality. These side shoots have the potential to become full, fruit-bearing stems, but allowing them all to mature often results in a dense, unwieldy plant. Managing this secondary growth through selective removal, a technique called pruning, is common practice for gardeners. Pruning helps create a more manageable plant and promotes larger, higher-quality fruit production.
Identifying Tomato Suckers and Their Role
Tomato suckers are small, new growth shoots that appear in a specific location on the plant. They emerge from the axil, the junction formed where a leaf branch meets the main, vertical stem. The sucker typically appears at a 45-degree angle, resembling a miniature version of the main stem itself.
A sucker has the potential to develop into a secondary main stem, producing its own flowers and fruit. If left unmanaged, the plant dedicates energy to this new stem, leading to a sprawling, bushy structure. This conflicts with a gardener’s goals for high-quality, large fruit.
Why Pruning Suckers is Necessary
The rationale for removing suckers centers on redirecting the plant’s energy from vegetative growth toward fruit development. Too many stems distribute available nutrients widely, resulting in smaller and less flavorful tomatoes. Selective pruning concentrates the plant’s resources into the primary stem and existing fruit, promoting faster ripening and increased fruit size.
Pruning also significantly enhances air circulation within the plant canopy, defending against disease. Dense foliage traps moisture, creating an ideal environment for fungal diseases like blight to spread. Removing suckers thins the plant, allowing more airflow to dry the leaves quickly after watering or rain. This reduces the risk of infection and helps manage the plant’s vertical growth, simplifying staking and harvest.
Step-by-Step Sucker Removal Techniques
The most effective approach is to remove suckers when they are small, ideally less than two or three inches long. At this stage, the material is soft, allowing for a technique called “pinching.” Use your thumb and forefinger to cleanly snap the sucker off as close to the main stem as possible, minimizing the wound size.
For suckers that have grown larger and become woody or thick, pinching is unsuitable, as tearing the stem could seriously injure the plant. Instead, use bypass pruners or sharp scissors for a precise cut. Sterilize your cutting tool with rubbing alcohol or a bleach solution before use and between plants to avoid transmitting pathogens. When removing a larger sucker, cut cleanly at the base, and avoid removing more than 30% of the plant’s total foliage at one time, which can cause significant stress.
When to Skip Pruning
The decision to prune suckers depends entirely on the specific variety of tomato plant. Varieties are categorized into two main groups: indeterminate and determinate. Indeterminate types are vining plants that grow continuously and benefit most from regular sucker removal to manage size and maximize fruit quality.
Conversely, determinate varieties, often called “bush” tomatoes, grow to a predetermined height and set their fruit all at once. The suckers on determinate plants contribute necessary foliage to protect developing fruit from sunscald. Pruning suckers from a determinate variety is discouraged because it reduces the total number of tomatoes harvested.