Tomato plants naturally grow as sprawling vines. When stems become heavy with developing fruit, they can bend and potentially break. Providing a support system prevents stem breakage and protects the plant from the physical stress of a heavy load.
Allowing foliage and fruit to lie on the ground increases susceptibility to soil-borne diseases and pests. Keeping the plant upright improves air circulation, which helps prevent fungal infections like blight and mildew. Vertical growth also maximizes sunlight exposure, improving photosynthesis and leading to a higher quality harvest.
Selecting the Right Support System
The choice of support depends significantly on the tomato variety: determinate or indeterminate. Determinate varieties, often called “bush” tomatoes, have a finite growth height, stop growing once fruit sets, and produce a concentrated harvest. Indeterminate varieties, or “vining” tomatoes, continue to grow and produce fruit until the first frost, often reaching heights of six feet or more.
Staking
Staking involves driving a single, sturdy pole—such as wood, bamboo, or metal rebar—next to the plant’s main stem. This method suits determinate varieties or indeterminate plants pruned to a single-stem habit. Staking promotes early harvest and maximizes sunlight exposure, but requires regular tying and pruning.
Caging
Caging provides support on all sides, making it an excellent option for indeterminate plants allowed to grow bushy. Standard store-bought cages are often too flimsy and short for mature, fruit-laden indeterminate plants. Building large, robust cages from concrete reinforcing wire with a six-inch mesh is a more effective alternative, offering heights of five feet or more.
Trellising
Trellising, such as string training or the “Florida weave,” is best for large gardens or intensive growing operations. This method uses a network of horizontal wires or twine supported by heavy-duty stakes or T-posts. Trellising is highly effective for vining indeterminate varieties, saving space by training plants upward and providing strong support for the entire row.
Proper Installation and Timing
The timing of support installation is a major factor in the system’s success and the plant’s health. The support structure should be installed early, ideally immediately upon transplanting the seedling into the garden. Waiting until the plant is large increases the risk of damaging the expanding root ball when driving the stake or cage into the soil.
Proper anchoring ensures the support can withstand the weight of a mature plant and resist wind stress. Stakes or cage supports should be driven deep into the ground, a minimum of 12 to 18 inches, to provide stability. This depth prevents the structure from toppling over later in the season.
When installing a stake or cage, drive it a few inches away from the plant’s base to avoid penetrating the developing root system. Root damage can stunt growth and compromise the plant’s ability to take up water and nutrients. For single-stake support, position the stake about three inches away from the main stem.
Ongoing Plant Training and Tying Techniques
Once the support is in place, ongoing training is necessary to guide the plant’s growth and manage its weight. When securing the vine, the choice of tying material is important to prevent stem injury.
Tying Materials
Soft, pliable materials are recommended. Avoid hard wire or thin, abrasive string, as they can cut into the stem as the plant grows thicker. Recommended materials include:
- Cotton cloth strips
- Specialized plastic tomato clips
- Natural fiber twine like sisal or jute
Tying Technique
The correct technique allows for future stem expansion without girdling the plant. A figure-eight loop or a loose circular tie is best. Wrap the material around the support first, then loosely around the stem. This method ensures enough slack to accommodate the main stem’s increasing girth. Ties should be checked regularly and loosened if they restrict growth.
Weight Management (Pruning)
Weight management is achieved through basic pruning, specifically the removal of “suckers.” Suckers are small side shoots that emerge where a leaf stem meets the main stem. Removing suckers directs the plant’s energy toward developing existing fruit and the main stem, rather than producing excessive foliage. This practice is beneficial for staked or trellised indeterminate varieties grown with a single or double-stem system.