Some controversy exists over whether or not tomato plants should be pruned, and the reality is that if you don't, it will not cause problems. Plenty of people do not prune at all and still grow good tomatoes. Tomatoes are not one of those plants that require pruning or deadheading in order to thrive, but shrewd pruning can improve the quality of the fruit you harvest.
Why You Should Prune Tomato Plants
The main reason to prune tomato plants is that it helps your plant direct its energy toward producing fruit rather than producing more foliage. Unpruned foliage will eventually grow into new branches that will form fruit, but most experienced growers advise that tomatoes should be pruned to not only produce larger fruit earlier in the season but also to protect the plants against pests and disease problems.
If you have fungal issues in your garden, airflow definitely should be considered, and you may want to prune your tomato plants. However, if your plants are not regularly bothered by leaf spots or other fungal issues, you probably don't need to worry about pruning.
Additionally, if your tomato plants are lying on the ground, you might want to prune them. When leaves are forced into permanent shade, such as when the bushy plants are on the ground, the amount of sugar they produce is reduced. Instead of pruning, you can also stake your tomato plant to keep the leaves off the ground.
When a tomato plant is pruned properly, all of the foliage receives adequate sunlight, and the plant is able to photosynthesize more efficiently, boosting growth and fruit production.
Before Getting Started
Not all types of tomatoes need to be pruned. If you are growing determinate tomatoes, you don't want to prune. Because determinate plants develop all of their fruit at one time, pruning may cause you to sacrifice tomatoes for no reason.
If you're growing indeterminate tomatoes, which produce fruit regularly over the course of a season, pruning is essential. This helps keep the commonly huge vines in control, and it encourages the plant to produce several large tomatoes instead of lots of foliage and many smaller tomatoes. To fit more plants into a small space, you'll want to prune your indeterminate tomato plants regularly and keep them staked or caged. This will prevent your plants from getting too large and bushy. However, indeterminate plants will still keep growing taller, and you'll keep getting fruit as long as the plant is growing.
Equipment / Tools
- Small pruning shears
- Stakes and twine (as needed)
- Household disinfectant
Locate the Suckers
Look for the tomato "suckers," which grow in the "V" space between the main stem and the branches on your tomato plant. If left unpruned, these suckers will eventually grow into full-sized branches, adding lots of foliage and, eventually, a few fruits. This will also result in a tomato plant that quickly outgrows its space in the garden.
Remove the Suckers
Suckers under 2 inches long can simply be pinched off with your fingers, but with larger suckers, use a pair of clean pruners, disinfecting them as you move from plant to plant to protect against spreading diseases.
Whenever possible, remove the suckers when they are small. Removing large amounts of foliage at one time can stress the plant.
Remove or Stake Long Branches
Branches that are low-hanging and touching the ground should either be staked up or removed. Leaves touching the ground can be susceptible to bacteria, fungi, and viral infections that can spread through the rest of the plant.
Pruning Tomato Plants. University of New Hampshire Extension