The conversations around pruning tomato plants can be dizzying! Some gardeners say definitely do, while others say don’t bother. And the methods vary as well: remove entire branches, cut just the tips of branches, prune at certain times, prune throughout the season, and so on. This can all leave you wondering not only how to prune tomato plants, but whether it’s worth doing in the first place.
To help you untangle all of the techniques and opinions, here is a straightforward guide to tomato pruning.
How to Prune Tomato Plants
Should tomato plants be pruned?
Although not technically necessary, pruning helps keep tomato plants tidy and healthy and stimulates fruit growth.
Reducing the foliage on a plant improves airflow, thus reducing the likelihood of diseases that often develop in the presence of excess moisture. It also directs energy away from leaf growth and toward fruit production, which is really the whole point of planting tomatoes in the first place!
Before you begin trimming your tomato plants, it’s important to know which type you have.
- Determinate varieties stop growing at a certain height, have a bushier habit, and produce fruit earlier but in a specific timeframe. These should only receive minimal pruning.
- Indeterminate varieties, on the other hand, will continue growing and producing fruit until frost. Because of their indefinite growth, they can be pruned rather vigorously.
When to prune tomato plants
Tomato pruning should occur in stages throughout the growing season. Below is a step-by-step list to walk you through the process, with a few more details in the sections that follow.
- When planting seedlings out in the garden, pinch or cut off any lower leaves that may come in contact with the soil. You may need to repeat this step later, as branches that initially seem high enough sometimes droop as they grow.
- Once the plants grow taller than a foot, begin removing suckers and any diseased or otherwise damaged branches. This process will continue throughout the growing season, especially for indeterminate types.
- About four weeks before the first frost, remove the growing tip of each main stem (indeterminate only). This signals the plant to stop flowering and instead finish ripening all of the fruit already on the vine. Even if they don’t ripen before frost, any green tomatoes you bring inside after “topping” the plant should fully ripen on the counter.
If your tomato plants are already large and wild, don’t worry! Remove all of the leaves about 12 to 18 inches off the ground and lower, then move on to step two.
Tomato pruning tools
If you prune your tomatoes regularly when the suckers are small, all you need is your fingernails to pinch them.
But, if you forget or don’t have time and you find yourself with long, thick suckers, you’ll need to use a pruning shear to ensure you don’t damage your tomato plant.
How to remove tomato plant suckers
Before pruning suckers, identify the lowest cluster of flowers (or fruit, if your plants are already mature), then the leaf directly under it. Start by pruning only below this point of reference. If you remove too much foliage above this point, you risk exposing the fruit to too much sun, which can result in sunscald.
Now that you know where to prune, you need to know what you’re actually pruning! A sucker is the new growth that appears between the main stem and a leaf. If you catch them when they’re small enough, you can simply pinch off the shoot at the base with your fingers. A sharp knife or pruner will help with larger suckers.
Many gardeners remove all suckers as they appear, even above the lowest flower cluster. If you choose to go this route, make sure that the remaining foliage will sufficiently shade all of the fruit, especially if you live in a hot, southern region. A good way to prune higher up without inviting sunscald is to pinch off only the leaflets at the end of each sucker, leaving the two base leaflets to shade the fruit.
Because indeterminate tomato plants continue to grow indefinitely, you will need to check regularly for new suckers. As you do this, look also for any diseased or otherwise damaged leaves and any that touch the ground, and remove these as well.
How to keep tomato plants from growing too tall
What if you planted an indeterminate variety but don’t want your tomato plants to grow above a certain height? To keep tomato plants from growing beyond your reach or above the height of their supports, simply pinch off the growing tip once the plant reaches the desired height.
This is also a great way to encourage late-season tomatoes to ripen before frost (see “When to prune tomato plants,” above).
What to do with pruned suckers and leaves
Never leave tomato clippings in the garden! Leaving clippings at the base of the plants can contribute to the spread of disease, so make sure to collect all of the leaves and suckers and dump them on the weed pile.
Another good practice to prevent disease spread is to clean your knife or pruners with an alcohol-based disinfectant after each use.
Tomato pruning FAQs
When should I trim my tomato plants?
Tomato plants should be pruned at the time of planting as well as throughout the growing season. For details, see “When to prune tomato plants,” above.
Can you prune tomato plants too much?
Yes, removing too much foliage can expose the fruit to too much sun and cause sunscald, and over-pruning may even result in reduced fruit production. To avoid this, prune mostly or even exclusively below the lowest flower cluster.
Do you pick the yellow flowers off tomato plants?
Typically, no, because the flowers will give way to fruits, and thus removing them prevents fruit production. However, some people recommend removing any flowers present when you plant tomato seedlings and until the plants reach about a foot high. This encourages the plant to put energy into growing strong, healthy roots and leaves at this early stage before its focus turns to fruit production.
Should I prune dead tomato leaves?
Yes, remove all dead leaves to improve airflow and prevent the spread of disease.
Will tomato plants regrow after being cut to the ground?
No, tomato plants will not regrow if you cut them back to the ground. They may sprout a few new leaves, depending on how much of a stump is left, but even then they likely won’t have enough time to grow and produce fruit before frost sets in. If you have the unfortunate experience of deer chomping off entire tomato plants, as I did one year, head over to your local greenhouse and take advantage of their late-season sale.
Once you untangle all of the advice available about pruning tomatoes, the process itself is really pretty simple. I hope this article has granted you some clarity and thus confidence to prune your tomato plants for a tidier garden and a bountiful harvest. Happy growing!