Tomatoes are known as the quintessential backyard crop for a reason. They’re easy to grow and almost everyone—from the greenest thumb to the greenest gardener—has at least a plant or two in their backyard. However, not even some of the most seasoned gardeners know that there’s a pruning method unique to tomatoes. So, follow along in this episode of Backyard Smart for the lowdown on how to prune tomato plants.
The Benefits of Proper Pruning
Proper pruning keeps your tomato plants happy and healthy. Instead of focusing on growing new leaves, a properly pruned plant redirects energy towards growing bigger, tastier fruit. The process also helps improve airflow in and around the plant. By removing unnecessary suckers, you make the plant less dense, allowing for more air to reach the stem—a vital part of keeping any tomato plant healthy.
If left to grow naturally, tomato plants can become a damp, tangled mess. Pruning makes it easier to identify pests (such as aphids, hornworms, and flea beetles, among others) that like to make a meal out of tomatoes. And, it helps your plants both dry out faster after rain and stay off the ground, avoiding ugly blight.
That’s not all! Routine pruning helps kick your fruit production into overdrive. Trimming off unnecessary or overgrown suckers lets you plant your tomatoes a little closer together. It also frees up energy to spur on earlier ripening and maximized production. Letting you enjoy even more backyard meals, all season long.
Indeterminate vs. Determinate Tomatoes
Knowing how to prune tomato plants is nothing without knowing the difference between the two types: indeterminate and determinate. While all tomato plants are vining, not every tomato plant needs to be pruned. Determinate tomatoes are more bush-like, growing to a predetermined height—typically around 2 to 4 feet—and stopping once the topmost buds set their fruit. Afterwards, all the fruit ripens and the plant starts to die, no longer growing or producing new tomatoes.
Because they only set fruit once and stop growing, pruning determinates is generally not needed. But, due to being the smaller plant, determinate varieties are perfect candidates for container gardening.
Indeterminate tomato plants are the more vine-like of the two, continuing to grow higher, and set new fruit, throughout the season. They can grow as tall as 12 feet, though most indeterminate varieties tend to stay around 6 feet, making trellises, cages, and stakes a necessity. Unlike determinates, fruit harvested from indeterminates will grow back all the way up until first frost, meaning they need regular pruning. However, they do require a bit more patience as they ripen later in the season, with their stems growing longer before setting fruit.
When to Prune
Always head out on a sunny morning to prune. Your tomato plants should be dry, with any dew or overnight rain having already evaporated. Wet conditions invite blight, so this reduces the risk of your plants contracting disease. And, it’s generally best practice to prune when the suckers (or the side shoots that grow in the “V” space between the stem and branches) are 2 to 4 inches long. This ensures that energy is properly directed and spent on the growth of new fruit.
Careful! Don’t prune too early in your plant’s growth cycle. Wait until the first flowers open and are easily identifiable. Otherwise, get to removing suckers as soon as possible. Stop pruning around 1 to 2 weeks before your first harvest to allow your plant time to grow leafy canopies to protect the fruit from sunscald.
How to Prune Tomato Plants
Pruning’s simple—just locate the suckers and remove them! If they’re under 2 inches in length, your finger and thumb is all you need. If they’re a little longer, pruners or scissors are the better bet. And if they’re even longer than 4 inches, start at the tip of the sucker and work your way in. This reduces any shock to the tomato plant.
Just like not every tomato plant needs pruning, not every part of the plant needs pruning, either. Make sure to leave the top third of the plant alone—this will continue to grow and produce fruit later in the year. Don’t touch the first sucker under the lowest flower or fruit cluster, either. This sucker is the strongest on the plant and will eventually bear even more fruit as a second stem.
https://hort.extension.wisc.edu/articles/tomato-pruning/
But before you get to pruning, make sure to disinfect your pruners or scissors and wash your hands. This’ll help prevent the spread of fungi, bacteria, and other viruses that can cause disease.
That’s it! Now get outside, get pruning, and help your tomato plants prosper. You’ll be enjoying the tasty fruits of your labor in no time.
