Pruning Tomato Plants For The Biggest Yields


Tomato plants tend to get messy and wild in the garden. If you don’t use a tomato cage or a trellis, the plants will sprawl across the ground, covering as much of the soil as possible. They will also likely become diseased, and produce smaller tomatoes.

One important task you can do to keep your plants healthy is to prune your tomatoes regularly. Pruning tomatoes can be a bit complicated at first. But once you understand the basic components of the plants, you’ll be a pruning pro in no time.

In this article, I’ll cover the basic anatomy of a tomato plant, the different types of tomatoes, and how to prune tomatoes properly. The goal of pruning is to reduce disease on your plants, increase the overall yield of quality tomatoes, and speed up ripening in some cases. Let’s get started!

Tomato plant growing in tomato cage with basil and alyssum trellis

Tomato Types and Anatomy

All tomatoes have 3 main types of growth:

  • Leaf branches. These grow directly off of the main stem and have a single branch with leaves on either side. The shape and size of the leaves can vary by the tomato variety. The goal of a leaf branch is to produce energy for the plant to grow by photosynthesizing.
Tomato leaf on plant
Tomato leaf branch.
  • Flower trusses. Flower trusses grow from the main stem of your tomato plant and are what hold the flowers and eventual fruits. These are almost never pruned off, unless they are very low on the plant, or attached to an unwanted sucker.
Tomato flower truss
Tomato flower truss.
  • Suckers. Also known as side shoots, suckers will form an entire new branch, usually between a leaf branch and the main stem. This new branch can produce more leaves, flowers, and even more suckers! Suckers will be a main focus of pruning, so learning to identify them is key.
Young sucker on tomato plant
Young sucker on tomato plant.

All tomato plants will produce these 3 main types of growth. However, the pattern of growth can be very different from one variety to another. There are 2 major categories of tomato types: determinate and indeterminate.

Determinate Tomatoes

Determinate tomatoes will produce all of their fruits at once. Roma is the most popular variety that is usually determinate. These varieties are best if you plan to process your tomatoes into sauce, since you get a huge harvest, all at one time. However, once the plants produce, there is rarely a second harvest.

Indeterminate Tomatoes

Indeterminate tomatoes will produce smaller harvests on a regular basis. Most cherry tomatoes, and many larger beefsteak tomatoes are indeterminate. The plants will grow continually in a “vine-like” manner. These plants can grow very tall when supported vertically, and tend to get very wild if left unpruned.

With these basics understood, you can get into the garden and begin pruning each plant appropriately. Let’s talk about how to prune each tomato type.

Pruning Cherry Tomatoes (Small Varieties)

Cherry and grape tomatoes are some of the most popular varieties to grow. Their small size makes them great for snacking right in the garden, and each plant can produce tons of tomatoes.

Recommended pruning:

  • Remove excess leaf branches to improve airflow
  • Remove a few suckers as needed for airflow, but leave most untouched
  • Bottom prune lower leaves to keep them off of the soil
Sun gold cherry tomatoes on truss
Cherry tomatoes on plant.

With cherry tomatoes, it is best to avoid over-pruning suckers. These side shoots can eventually produce more full-sized fruits, which increases the overall yield. However the plants can get very big and stuffy, so it is helpful to prune every 1-2 weeks to improve airflow.

You can also remove suckers and leaves as needed to shape your plants and keep them an appropriate size for your garden. It’s common for cherry tomato plants to spread out when left unchecked!

Bottom pruning (recommended for all types)

Bottom pruning is the simple task of remove the first 8-12 inches of leaves from the bottom of the plant. Do this in the mid-spring after your plants are established outdoors. This improves aeration around the base of the plant. More importantly, it reduces soil splashing onto the lower leaves, reducing the chances of soil-borne disease.

Pruning Indeterminate Tomatoes (Large Varieties)

If you’re growing bigger tomatoes, like heirloom slicing tomatoes or beefsteaks, then a bit more pruning is recommended. While you can let your plants grow wild, you’ll likely have better results if you prune regularly.

Recommended pruning:

  • Prune suckers regularly, keeping 1-2 main stems
  • Prune overlapping leaf branches to reduce disease/improve airflow throughout
  • Prune lower flower trusses that are below your tomato cage line (heavier tomatoes should be supported)
  • Bottom prune lower leaves to keep them out of the soil

Larger tomato varieties can only produce so many fruits at one time. If you allowed every sucker shoot to form, your plant would struggle to produce full-sized fruits on all of them. Instead, I recommend pruning most of the suckers (and there will be many), keeping one or two main stems.

The result is a taller, slender plant that is supported by a stake or tomato cage. This makes it easier to space tomato plants closer together, and will improve the size and quality of your tomatoes in the end.

Pruning Determinate Tomatoes

If you are growing any determinate tomato plants, pruning is much different. These varieties only produce a single crop, so you want to get the most out of each plant.

Recommended pruning:

  • Remove excess foliage to improve airflow
  • Do not prune suckers, as they will increase the number of tomatoes at harvest
  • Bottom prune lower foliage and flowers to improve airflow and reduce soil splashing
Tomato plant growing in tomato cage with basil and alyssum trellis

The main different in pruning determinate tomatoes is that suckers are not removed. The side shoots will increase the plant’s mass, and can increase the number of flower trusses. This leads to a larger yield when the plant produces its crop. Since you only get one shot at a harvest, it is better to have as many branches and flowers as possible.

The only type of pruning I’d recommend is thinning the foliage for improved airflow. Tomatoes are vulnerable to disease, so removing leaves that are overlapping can help reduce the development and spread of disease.

Now that you know the basics of pruning, time to form a plan! Get out in the garden and start getting familiar with the anatomy of your tomato plants. Once you have the hang of it, pruning tomatoes becomes second nature.

One Comment

  1. Thank you for your help and am very happy to hear this knowledge of plant pruning especially on tomatoes

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