How to Prune Tomato Plants: 7 Steps for Success

Figuring out how to prune tomato plants is one way to decrease tomato diseases and create better quality fruits.

I never realized that learning how to prune tomato plants is a vital part of having a large tomato harvest each year, but once I figured this out, I’ve had more success with my tomato plants than ever before.

Indeterminate tomato plants continue to grow, reaching impressive heights and width. However, your plants don’t need to be massive to produce fruits. Pruning your plants keep them within a reasonable size for your garden.

Plus, it helps to prevent tomato diseases.

Some years, my tomato plants would be so large that I couldn’t harvest everything. You can’t harvest what you don’t see! I would have dead or dying branches that need to be removed, but I couldn’t find them to take them off.

Trust me, pruning your tomatoes is a big deal, and it makes it much easier to take care of your plants. I consider it one of the best tomato-growing hacks.

Here is what you need to know about how to prune tomato plants.

Do You Need to Prune Tomato Plants?

Pruning tomato plants is optional, but in my opinion, it’s a necessary step to help keep your plants managed and reduce diseases that might come from soil-borne bacteria.

The one caveat is that you should typically only prune indeterminate tomato varieties that produce new leaves and flowers throughout the growing season. Determinate tomato varieties aren’t recommended for pruning because you could reduce your harvest.

The years when my tomato plants struggled the most were the years that I didn’t prune as I should have.

If you’re wondering – do I need to prune my tomato plants – ask yourself these questions.

• Do your tomato plants end up wild and out of control by the end of the growing season?
• Are your tomato plants consistently plagued by different diseases?
• Do your plants flop over and overwhelm other parts of your garden?
• Do you feel like your tomato harvests are less than ideal?

If you answered yes to any of these, I highly suggest you try pruning tomato plants this year.

The Benefits of Pruning Tomato Plants

When I first started gardening, I had no idea that I should prune tomato plants, but as I learned more about gardening, I realized I was missing an important step. It helps my plants grow stronger, and the harvests are always larger.

Here are some reasons why you definitely want to prune tomato plants.

Fewer Diseases

When your tomato plants have fewer leaves, it allows air to circulate more throughout your plants, allowing the leaves to dry faster after rain or watering. That means they’re less likely to experience fungal diseases; if you live in a wet climate, that’s particularly helpful.

Another reason why pruning tomato plants helps to reduce diseases is that the leaves don’t touch the ground. Many diseases and bacteria live in the soil, and when your tomato leaves touch the soil, it gives the diseases an entry point into your plant.

This is a big problem that my tomato plants faced. Whenever I had leaves on the ground, I ended up with tomato plant diseases.

Bigger and Better Fruits

I noticed that when I regularly prune my tomato plants, I end up with bigger and better fruits at the end. That’s because pruning encourages your tomato plants to send more energy towards ripening fruits rather than making more leaves.

You might have fewer fruits but they’ll be larger and better quality. Also, since you can plant more prune tomato plants, keeping them closer together gives you a chance to end up with more fruits than you’d end up with otherwise.

Saves Space in your Garden

One of the most important reasons that I prune tomato plants is that it helps to keep the plants more compact, so I can plant them closer together. I don’t have a lot of gardening space compared to other homesteaders, so even inch matters and needs to be used in the best way possible.

Pruning lets you fit more plants in your garden, and that means more tomatoes that I get to preserve from my garden. There are so many different ways to preserve tomatoes, so I want to take advantage of this the best that I can.

Earlier Ripening

Pruning removes leaves – duh – and that means your plant has fewer leaves and branches to worry about, so it sends more energy into ripening fruits faster. If you live in a short season, that can be incredibly helpful!

When Do You Prune Tomato Plants?

You should start pruning your tomato plants as soon as you plant them in the ground. Prune off any lower branches when you transplant your tomato seedling into your garden. Then, wait until your tomato plants are one to two feet tall before pruning off more leaves and branches.

Understanding the Parts of a Tomato Plant

Before you start pruning, I suggest that you identify the different parts of the tomato plant. You don’t to accidentally cut off the wrong thing. Let’s go through the parts of your plant.

1. Find the Main Stem

First, you want to find the main stem of your plant. This is the stem that comes out of the ground and goes to the top of your plant. The top of this main stem is how your plant continues to get taller.

Never ever cut off the main stem of your tomato plant.

2. Look for the Branches

Move up the main stem and look for the branches that come off of your tomato plant. These are where you’ll find the next two parts of your tomato plant.

3. Look for Fruit and Flower Clusters

Tomato plants have flower clusters – groups of yellow flowers – and fruit clusters – groups of tomatoes already forming. This is where you’ll harvest your fruits. You don’t typically want to remove these after the middle of the growing season.

4. Identify The Leaves

Look for the leaves on your plant. These are connected to the main stem and branches throughout your plant. Leaves collect sunlight and turn it into energy for your plant, but it’s possible to have way too many leaves as well.

5. Find the Axil and Suckers

When you research pruning tomatoes, you’ll see a lot of discussion around suckers. These form in the axil, which is the space between the main stem and an offshoot branch. Suckers grow straight up, looking like a smaller leaf.

These will grow into larger parts of your plant with leaves, flowers, and even suckers! They essentially create a whole new tomato plant on your plant. It’s best to prune off some or all of the suckers on your plant.

How to Prune Tomato Plants

Pruning tomato plants doesn’t happen at just one time. You need to prune at several times throughout the growing season to truly reap the benefits. I suggest pruning when you plant in the spring, in the middle of the growing season, and at the end of the season.

Here’s the steps to properly prune tomato plants.

1. Prune When You Plant

When you plant your tomato seedlings, remove any of the lower leaves because it allows you to plant them deeper into the soil. If you see any flowers, make sure you remove them as well, which tells the plant to send more energy into growing leaves not fruit.

2. Prune Again When The Plants are in Early to Mid-Season

By this time, your tomato plants are 12-24 inches tall, and it’s time to prune again. Start by removing flowers; you want your plants to send more energy into roots and growth at this time.

3. Remove Suckers

This is the time that you need to start removing all leafy suckers so that they won’t slow the development of the fruit. Suckers are little shoots that form in the axil, a spot where the leaf stem attaches to the main growing stem.

There is a lot of controversy about removing suckers – crazy right?

Leaves are necessary on your tomato plant. You never want to remove too many because leaves are how your plant takes in sunlight that is then converted into energy for the plant to grow. So, if you remove too much, your plant won’t have the access to the sunlight to grow.

How much of the suckers you remove will depend on where you garden. I’m a northerner garden, and I remove around 3/4 of the suckers on my tomato plants. However, southern gardeners tend to leave more on the plant because they provide shade to developing fruits. Tomatoes are vulnerable to sunscald.

I suggest removing different amounts of suckers on your tomato plants to see what works best for your area and garden.

When removing suckers, find fruit and flower clusters on your plant and remove the suckers that are near the clusters. These are sucking energy away from growing the fruits larger, but you don’t want to remove any suckers directly under the first fruit cluster!

Don’t toss out those tomato suckers. You can root tomato suckers and end up with new tomato plants for your garden!

4. Remove Anything Touching the Ground

As I mentioned before, when your tomato leaves and branches touch the ground, it leaves the plant vulnerable to diseases. I recommend pruning off any leaves that are touching the ground.

Even if you have determinate tomatoes, it’s suggested that you remove lower leaves to stop soil-borne diseases from splashing onto your foliage. Simply clip away these leaves and continue pruning up to a foot off the ground.

5. Prune Any Dead, Diseased, or Dying Branches

No matter when you prune tomato plants, you always want to remove any dead, diseased, or dying branches. These are an energy drainer, and you have no reason to keep these on your plant.

Take them off!

This is another pruning step that both indeterminate and determinate plants benefit from; there is no need to keep these on your plants. Plus, one way to stop the spread of diseases throughout your entire plant is to cut the diseased branch off the plant entirely.

6. Consider Opening the Middle of the Plant

If your plants are supported by cages, like mine, removing a few of the inner leaves help to increase airflow. The more airflow that your tomato plants have, the less likely it is that your plants will end up with a tomato fungal disease.

However, when you do this, don’t take away the leaves that are closest to tomato clusters. Experts say that the leaves closest to a fruit are the ones that send the sugar to the fruit, so you don’t want to do that.

7. Prune Again in the Late Season

When the growing season is coming to an end, your tomato plants probably have a lot of fruits on the branches. You want to speed up the ripening process during this late season stage by removing the growing tip of each main stem around four weeks before the first frost date in your area.

Removing the growing tip is a process called topping; it’s a type of pruning that makes your plant stop flowering and setting new fruits. It causes your fruits to ripen faster if you don’t want to bring your green tomatoes inside to ripen.

6 Tips for Successful Tomato Pruning

1. Remember to Only Prune Indeterminate Tomatoes

I have to say it again – never prune determinate tomato plants. These only reach a specific size, and you risk severely damaging your tomato plant if you prune these tomato plants. Only take off leaves that touch the ground, along with any branches or leaves that are diseased or dying.

2. Use Sharp Garden Scissors

Using sharp, garden scissors is the best choice when pruning tomato plants. Dull scissors make it so you won’t have a clean cut, and you could risk ripping the plant.

Garden scissors aren’t expensive. I like this pair of Gardening Hand Pruners by Vivosun. The price is under $10, and they stay sharp in my experience. I also like that these garden scissors have a micro-tip that lets me get into small spaces when pruning.

3. Clean Your Scissors Between Plants

Make sure you clean your scissors between pruning each plant. I use hot soapy water or diluted bleach. The reason you need to clean your scissors is that if one plant has a disease and the other doesn’t, you could spread the disease to your healthy plant.

4. Never Work with a Wet Tomato Plant

Working with a wet tomato plant is never a good idea. This increases the risk of spreading diseases in your garden.

5. Over Overpruning Your Plants

Pruning too much of your tomato plants is never a good idea. Your plant needs leaves to generate energy, and if you remove too much, you can cause a lot of problems.

Overpruning causes your plant to be stressed, which could reduce the harvest you receive. Your plant might stop growing entirely, and your fruits could end up being burned by the sun if they don’t have any shade in the plant.

So, I suggest pruning a total of no more than 1/3 of your plant entirely, breaking that down into different pruning times throughout your gardening season.

6. ALWAYS Mulch Your Tomato Plants

You need to apply a layer of mulch underneath your tomato plants as soon as you plant the seedlings. Mulch has several benefits.

• It stops bacteria and diseases from splashing onto the lower leaves from the soil.
• Mulch retains moisture, so you don’t have to water your plants as often.
• It suppresses weed growth, so you don’t have to weed as often.
• Mulching helps to regulate soil temperature throughout the growing season.

Pruning is Essential

Don’t wait to learn how to prune tomato plants; it’s easier than you think. Experiment with your plants, pruning more or less, to find out what works best in your garden.