How to Prune Tomato Plants, Peppers, Cucumbers and More

If you’re new to vegetable gardening, you might see the six-pack of tomato sprouts at your local gardening center and think, “Wow, what a deal!” What you might not realize is just how big tomato plants grow. I’m 5’6,” and my indeterminate tomato plants are usually at least as tall as me. 

Letting your tomato plants grow all willy nilly isn’t an option either, you need a tomato tower, which allows them to grow upward and contained, rather than toppling all over one another for months until they die. Knowing how to prune tomato plants is key to making the most of your bounty. 

Assuming you’ve planted your tomatoes nicely spaced apart (at least two feet, but I recommend three), and your tomatoes are growing upward, not flopping on the ground, you might still be noticing that your tomato plants are reaching for the sky. And if you already see a bounty of green tomatoes starting, it’s reasonable to be concerned that your pregnant green friends will begin to get unruly.

The good news is that not only can you prune tomato plants, but done correctly (aka not killing them) will give you bigger, better tomatoes. If you’re wondering how to prune tomato plants for maximum yield, follow the tips below.

But first, if you’re pruning multiple plants, make sure to clean your pruning shears with alcohol in between, so that you don’t spread any disease from one plant to another.

How to Prune Tomato Plants Like a Boss

You’re the boss, not your tomato plants! If you over-planted, it might seem daunting, but learning how to prune tomato plants is easy, and honestly, if you don’t do it, your plants will probably be fine. 

We have a complete guide to pruning in our Tomato Collection, so I’ll keep this light. I’m going to give you a quick primer here, along with ways to prune other vegetables, which are all much easier than tomatoes. Learning how to prune tomatoes will actually help you more quickly discover how to prune different types of vegetables, which is why we’re starting here.

The most important thing you need to know about how to prune tomato plants is how to identify the “suckers.” These are the branches of your tomato plant that can either drain energy when left to grow, or give it to the tomatoes when they’re trimmed off.

To find the suckers, look at your tomato plant. You have the main stem, and then you have a regular branch. At the axis between the stem and branch, an extra branch often pops up, which is called a sucker. These are easiest to identify when the plant is still young. If you let them grow, they’ll just grow flowers and tomatoes, so they’re not a danger, but if you prune them off, your plant will have better aeration and will grow bigger and better tomatoes on the rest of the plant.

Early Pruning:

Ideally, prune early in the season, before the plants start getting unruly, where you can easily find the suckers and differentiate them from the central stalk.

• Use garden clippers to trim off the bottom branches from the lower 6″, to avoid disease from the soil from getting onto the leaves, and also to give you room if you’re companion planting, such as planting basil around your tomato plants.
• Determinate tomatoes (those with a limited growth size and production season) will generally be topped with flowers or flower buds. You can lop the suckers off, anywhere below the first bud you see, and this will help with aeration.
• Indeterminate tomatoes (those that produce throughout the season and can grow for many months in warmer climates) have a longer season and really don’t need to be pruned to start, however if you choose to prune indeterminate tomatoes, all you need to do is find the suckers and remove any that don’t seem beneficial, like those at the base, or those that are making the plant too bushy to aerate.

Mid-Pruning:

• If your tomato is unruly, and you have an indeterminate tomato (don’t prune unruly determinate tomatoes once they start producing), you can still clean up by removing suckers. However, since they’re larger and well-grown now, you’ll have to be more careful not to lop off any tomatoes. Do this when you’re not expecting rain, and in the morning when it’s sunny so that the cuts will try up quickly without letting in disease.
• Like in early pruning, you can clip off any stems with leaves touching the ground or those that are growing out of control by pruning them right at the main stem. 
• You can get pretty aggressive with pruning indeterminate tomatoes, just leave any stems that already have tomatoes growing. 

Late Pruning:

• When the season is nearing its end, prune the tops of your indeterminate tomato plants so that they stop growing and creating new tomatoes so that they start producing bigger tomatoes on the bottom branches before the plant dies.

How to Prune Pepper Plants

Pruning pepper plants isn’t entirely necessary, however, if you choose to do it and try to grow bigger peppers, you can prune off the top if it hasn’t flowered yet. Cut above existing stems, so that they turn into the new head of the pepper plant, and it will bush out instead of growing taller.

How to Prune Cucumber Plants

You really can get a bigger bounty by pruning cucumber plants. You’ll understand why I started with tomatoes when I tell you that all you need to do to prune cucumber plants is to find the suckers and pick them off. 

How to Prune Eggplants

Eggplants are pruned very similarly to tomatoes. You don’t want them to be bushy at the bottom, so find the suckers (mentioned above if you skipped ahead) and clip them off, along with any leaves touching the ground. 

How to Prune Zucchini Plants

Other than increasing production, one of the reasons to prune zucchini is to trim off any leaves that may be infected with powdery mildew, which is pretty much a given if you’re growing zucchini. Use gloves to avoid the prickers, and prune off any old, yellow leaves right at the stem, and make sure to remove them from the garden to avoid spreading any disease.

How to Prune Asparagus

Unlike the others on this list, asparagus is pruned in the fall after it has died, and is dry and brown. Use pruning shears to cut down to about 1″ high. The asparagus ferns make great compost.

How to Prune Pumpkins

Pumpkins can get especially unruly and take off out of your garden and into your yard if you let them. It might seem cute and fun the first year, but it’s a real pain to clean up afterward. Additionally, you can get bigger pumpkins if you keep the vines tamed. To prune pumpkin vines, cut the vine a couple of inches, right above the last pumpkin flower that you want, so that it stops growing. Just be sure that you’re leaving at least 10-15 feet of the vine. And if you’re looking at a secondary vine offshoot, trim off any shoots from the secondary vine. 

What other types of vegetables would you like to know how to prune? Do you better understand now how to prune tomato plants?