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How To Prune Tomato Plants – And Why It’s So Important!

One of the most important tasks gardeners can do to keep their tomato plants strong, healthy and productive is to prune them not once, but multiple times throughout the growing season.

There are a whole slew of reasons why pruning is vital. Not only does it significantly reduce the risk of disease and pests, but it also improves air circulation within the plant. That promotes better pollination, helping lead to a bigger and better harvest.

In addition, pruning also helps to minimize daily maintenance chores. For example, because there are fewer lower limbs it makes watering and fertilizing at the base of the plant much easier. In addition, any small weeds that poke through the ground will be easy to spot and remove. This in turn also prevents ground dwelling pests easy access to climb up the plant.

how to prune tomato plants
When and how you prune your tomato plants plays a crucial role in growing great tomatoes.

However, when it comes to how to prune tomato plants there are several aspects that can leave gardeners a bit confused. Which branches do I need to remove? Do I only cut the sucker branches? What if the branches already have blooms and/or small tomatoes forming? And – if my tomato plants grow too tall, should I cut the top branches off?

Today’s article has all of those answers and more to help know when, how and what to prune off your tomato plants so that you can have a larger harvest than ever!

How To Prune Tomato Plants

When it comes to how to prune tomato plants it is best to explain the process by the location of the branches themselves. In this case, we are talking about the lower portion of plants, the mid section and the top. As it turns out, each of these three areas will require a slightly different method when it comes to pruning.

The Bottom Of Tomato Plants – Why Pruning Up Is Vital

The single most important pruning task you can do for your plants is to prune the bottom branches. It will not only get your young transplants off to a healthy start, but it is also the key to keeping your plants strong and productive throughout the season.

If you keep the branches and leaves away from the soil, it lessens the chance of soil borne diseases such as tomato blight infecting your plants.

Rain and watering can splash blight spores up onto the leaves, starting an infection that can quickly climb the plant and lead to disaster. And if the lower limbs are still on, it’s easier than ever for them to find a spot to infect and spread. See our article: How To Stop Blight By Growing Blight Resistant Tomatoes

pruning tomato plants at base
The first stage of pruning is to clear the bottom area away from the soil. This will help keep soil borne disease and pests away from your plant.

However, there is another reason that bottom pruning is beneficial – air flow. By removing those bottom branches you create space for better air circulation. This helps dry wet foliage, decreasing the chances of mildew and fungal diseases.

Even better, the extra airflow makes it easier for pollinators and / or wind to reach your blooms. This, of course, is perfect for setting the stage for more tomatoes than ever!

Bottom Pruning Techniques – How High To Prune Tomato Plants

When it comes to how much to prune up from the bottom of your plant, it all depends on what type of tomato you are growing. For more compact varieties like Amish Paste, Roma, and San Marzano tomato plants, remove any branches that are between the ground and 1 foot in height.

For taller, indeterminate tomato varieties like, Big Boy, Brandywine and Beefsteak tomato plants, prune at least fifteen to eighteen inches up from the soil.

Having only one single stem at the bottom of the plant makes it easy for you to water and fertilize right where the plant needs it most – at the base. Once the plant begins to grow, remove the first few branches closest to the ground. Then as the plant continues to grow and mature, prune to the height needed for the variety of plant that you are growing.

mid section pruning
Prune your tomato plants gradually as they grow to promote good health and productivity.

Mid Section Pruning – How To Prune Tomato Plants

When it comes to pruning the mid (or center) section of your tomato plants, the goal here is to promote good air flow. Clearing some of those middle branches also allows adequate light to enter the center of the plant and promotes healthy growth and faster ripening.

For starters, cut back any stray branches that are reaching over to the plant next to it. Then trim out a few middle branches that are crossing over branches that are already producing blooms or have small tomatoes growing. This will allow for light and air where it is needed most.

Although sometimes impossible, when pruning in the middle section try to select branches with little to no flowers on them. In addition, be sure to remove weak or short branches that are in the way of other already producing stems.

There isn’t an exact science to pruning the mid section, so it’s important not to stress too much. At the very least, try to remove a few branches to allow for a bit more air and light.

Top Pruning – How To Prune Tomato Plants

If you grow large, indeterminate tomato plants, you may also need to prune a little of the top growth. This is because tomato plants can grow well above six feet in height. By the time that they reach this height, they are usually no longer getting support from tomato stakes or cages.

top pruning tomato plants
Trim excessive foliage and stems at the top of your plant if they are getting too tall.

Towards the end of garden season, this top area is not likely to produce tomatoes that will ripen before the first frost date hits. Therefore, by removing the green growth, you are allowing the plant to focus its energy on the fruit already on the vine and not for excess unnecessary growth.

Always Prune Away Disease & Damaged Branches

As your tomato plants grow you may notice that some leaves and branches have signs of disease or are damaged. You want to prune any branches that show signs of black spot. But also those that are turning yellow and dying off.

By removing them you are helping to stop the rapid spread of disease. This is not only true for the plant you are pruning, but also from spreading it to nearby plants. Never place these limbs into a compost pile or leave them in the garden.

Other Helpful Tips When You Prune Tomato Plants

When it comes to pruning tomato plants be sure the blades on your hand pruners or garden scissors are sharp. This will ensure that you get a nice clean cut and don’t tear the plant’s stem. Affiliate Product Link: Premium Titanium Bypass Pruning Shears

Also, make sure also you wipe down your blades to disinfect them between pruning each plant. Blight and other diseases can easily be transferred if using the same shears without cleaning them first. Use a general sanitizing or chlorine wipe to wipe the blades clean as you move from plant to plant.

shears cutting of branch of tomato
Be sure to wipe down our pruning shears to prevent the spread of disease between plants.

Finally, the best time of day to prune tomato plants is early in the morning. This is the time that the plants have the least amount of stress. However, if you can’t do it early in the morning, the second best option is late evening. Just be sure to do this after the temperature begins to cool down.

Here is to pruning your tomato plants this year and to growing your best crop of tomatoes yet!

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