The main goal of growing tomatoes is for them to produce as many ripe fruits as possible. If you are growing indeterminate or "spreading" varieties (e.g. Beef Master, Big Boy, and most heirlooms), prune the plant to remove unwanted shoots and leaves so that all the nutrients go to the tomatoes. If you are growing a determinate variety (such as Heinz, Biltmore, or Patio), over-pruning will be counterproductive. Get started with Step 1 below to learn when and how to prune tomato plants.
Step
Step 1. Determine the tomato variety you are growing
Before doing pruning, know in advance your tomato plant, whether the variety is determinate or indeterminate. Indeterminate varieties grow vines, and must be provided with stakes (buffers) to be upright and must be pruned in order to grow optimally. The determinate variety can sustain itself before growing into a bush. This variety naturally focuses its energies on fruiting without requiring too much human intervention. Here are some examples of tomato plants of each variety:
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Indeterminate:
Big Boy, Black Prince, Beef Master, German Queen, almost all cherry tomato varieties, and most heirloom varieties.
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Determination:
Amelia, Ace 55, Biltmore, Better Bush, Heinz Classic, Heatmaster, Mountain Pride and Patio.
Step 2. Find the sucker you want to trim
Look for new small branches that appear at the junction of the branch with the stem on indeterminate tomato plants. These tiny branches, called "stem shoots," should be removed. Stem shoots that are not pruned will take energy from the plant so that the resulting fruit becomes less. This isn't a bad thing, but strategically removing stem shoots will help your tomato plant to produce big fruit throughout the season.
Before taking any action, wait for the stems and leaves under the first flower arrangement to turn yellow
Step 3. Remove all the stem and leaf buds that are below the first flower bunch
It doesn't matter what type of tomato plant you're growing, just do this thing. This makes the plant strong because it grows with a sturdy middle stem. This action allows most of the nutrients to flow toward the fruit, instead of being wasted on unwanted parts of the plant.
- You can remove stem shoots by cutting off the tips of the growths with your index finger and thumb and bending them back and forth until they are neatly cut. This should be done when the shoots are still flexible and young. These small wounds will heal quickly. This technique is called "simple pruning".
- For leaves and stems (not leaf buds) that appear below the first flower bunch: If you live in a warm area, leave it alone until the leaves and stems turn yellow. Both are important parts to help shade the soil until the plant reaches maturity. On the other hand, if you are growing your tomatoes in a humid environment (such as a greenhouse), prune anything below the first flower bunch for good ventilation. Humid air makes it easy for diseases to grow and develop. Moisture also causes wounds that occur because pruning takes longer to dry so the plant will be more susceptible to disease. By increasing ventilation, plants will be better protected.
Step 4. Leave thick shoots
Do not prune thick stem shoots as this can damage the entire plant. If it's thicker than a pencil, use the "Missouri pruning" technique and trim only the tip of the stem, leaving a leaf or two to allow photosynthesis and protect the fruit from sun exposure. The downside, there will be stem shoots growing from the stems that are not pruned so you will have to re-prun them later. This is a good technique if you have to handle a lot of leaf shoots. If the pruning wound is attacked by disease, its location is far from the main stem. This method is also done by leaving a few centimeters of stem shoots so that the plants are not too shocked.
Prune stem shoots throughout the season to keep the plant healthy. Stem shoots can grow quickly, so you should trim them once or twice a week
Step 5. For indeterminate tomato varieties, leave 4 or 5 fruit bunches and discard all the rest
This is a branch that grows from the main stem above the first flower bunch. By leaving only four or five bunches, you will have a large, healthy fruit. If left more than that, the fruit will be small and the yield is small. Keep four or five strong bunches, then remove all side shoots, leaving the shoots at the top of the plant intact. This is what is called a terminal bud.
- Make sure you tie this vine-like plant to the stake after the flowers appear. Otherwise, the plant will spread over the ground and not produce healthy tomatoes.
- Determinate plants already have a predetermined number of stems to grow naturally, so you don't need to prune above the flower bunches. If you do pruning above the flower bunches, the branches that produce fruit will be lost so the plant can't even produce fruit.
Step 6. Remove yellowing leaves
Yellowing leaves will absorb more sugar than the leaves produce. When the plant begins to mature, naturally the leaves at the bottom will begin to wither and turn yellow. This is perfectly normal, and pluck the leaves when they appear. This keeps the plant fresh and free from disease.
Step 7. Prune the top of the plant
To get the best results from plants late in the season, trim the tops of your plants. Prune the terminal shoots when the tomato plants reach the top of the greenhouse. At this point, the growing tomato plant has had very little time to reach maturity. So all the nutrients should go directly to the fruit.
Tips
Determinate or "bush" tomato varieties do not need pruning (or in this case tied to stakes). This plant naturally grows short and dense, which will produce one "wave" of fruit in a two-week period, then die. Indeterminate varieties, also known as "vines" tomatoes, can grow as tall as humans, and produce fruit and grow throughout the season. The varieties of determinate tomatoes that people commonly grow are Roma, Rutgers, Celebrity (some call them semideterminate tomatoes), and Marglobe. Indeterminate varieties that are often grown are Beef Master, Big Boy, almost all types of cherry tomatoes, Early Girl, as well as most heirloom varieties
Warning
- To prevent tomato plants from becoming infected, it's best to use your hands instead of a knife to remove the shoots (wounds that occur can easily become infected). However, for tougher, older shoots, you may need to use a knife. If you must, sterilize your trimmer thoroughly after each use.
- If you smoke, wash your hands thoroughly with soap and water before handling tomato plants. Tobacco smokers can easily infect tomato plants with the "Mosaic Virus".
