It’s simple…. You’ll get the greatest yield when you learn how to prune tomato plants. Growing tomatoes is somewhat akin to growing bonsai.
It takes quite a bit of care and attention to train your plants and manipulate fruit production.
When done correctly, you will be greatly rewarded with larger fruit that actually ripens quicker.
In this article, we will share information to help you enjoy your tomato growing experience with smart pruning. Read on to learn more on how to prune tomatoes.
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Before You Plant Tomatoes, Choose the Right Tomato Variety
Right at the outset, it’s very important that you understand the difference between determinate and indeterminate tomatoes.
Determinate types of tomatoes grow to a determined height, usually about 4 to 5 feet tall, and they do not grow any taller than that.
You should not prune determinate tomatoes. Pruning determinate plants will reduce tomato production rather than increasing it.
Indeterminate tomatoes grow as tall as they possibly can. If given space and trained, the indeterminate plant will just keep growing upwards endlessly. These are the tomato vines you want to prune.
Skillful pruning of indeterminate tomato plants will result in a healthy and abundant crop.
Have Good Support In Place From The Start
When you plant indeterminate tomatoes, you should begin with a method of support in place.
For good tomato production, you need to stake tomato plants with high trellises, stakes, or sturdy rope to support them as they grow tall.
Tomato plants firmly supported allow you to plan your pruning and to carry it out with a clear vision.
As you work with staking tomatoes, you will support the main stems and trim away the auxiliary stems or tomato suckers.
With your plants and your support system in place, you will want to begin your plant pruning project. Be careful not to prune away main stems or excessive amounts all at once.
Remember, your tomatoes need to have good leaf structure for proper photosynthesis.
The main thing you want to do is trim away suckers (vegetative growth) that sprout out between the main stem and producing stems.
What About Tomato Plant Cages?
You won’t want to use tomato cages like these for this type of project as the cages tend to hold all of the limbs together.
Cages make it difficult to work around and determine which need pruning and which limbs should remain on the plant. Cages are far more suited for bush tomato determinate tomato varieties than non-determinate.
Why Does Pruning Work?
When you carefully prune and trim away nonproductive suckers and leave healthy, producing limbs in place.
Pruning tomato plants like this will put the majority of their energy toward fruit production and not expend energy on vegetative growth producing more and more leaves.
The suckers that appear between the main stem of the plant and producing stems are in essence new tomato plants.
The suckers take a lot of energy away from the plant reducing the ability to produce fruit being produced by the main limbs.
With good airflow plants and leaves easily dry quicker after rain and watering.
Reducing the number of leaves on your plants also makes it easier for you to control pests. Very simply put, you can see them more easily when they have fewer hiding places.
Fewer leaves also means more abundant sunshine to your plants and your fruit. This adds up to early ripening. This is very helpful in areas where the growing season is short.
Indeterminate tomatoes tend to sprawl quite vigorously if not pruned. They continue to grow, spread and take up a lot of space.
Carefully pruned and trained tomato plants take up far less space in your garden. This means that you can plant more and plant them closer together.
Even though your individual plants may have fewer tomatoes, these tomatoes will be larger. The fact that you can successfully grow more plants in the same square footage means that you will have a bigger crop.
Exactly How Do You Prune Tomato Plants?
Pruning methods vary somewhat from one gardener to another.
Some use a technique known as Missouri pruning. With this technique you begin by removing any blossoms that may be on the plant when you plant it.
This gives the plant energy to recover from transplanting and to develop leafy growth early on.
Follow-up by continuously pinching off the growing tips of the limbs leaving just the two bottom leaves.
Continue removing flower clusters until your plants reach about 18 inches high. This will ensure your plants develop strong roots.
When your plant develops its first flower cluster of tomatoes, examine it and cut off leafy suckers growing below that fruit cluster. As your plant grows taller, continue cutting off leafy suckers.
Always cut off below producing limbs. Remember, the leaves growing closest to fruit clusters are the ones that deliver sugar to the fruit.
For this reason, when you prune your plants don’t cut off the leaves surrounding the fruit cluster.
These leaves not only provide valuable sugar to the fruit, they also help to shade it from the damaging rays of the sun known as sun scald.
Tomato Pruning For Northern Gardens
Missouri pruning is a good method for warmer climates, but in colder climates it’s better not to wait until the plant grows to 18 inches to begin cutting off suckers. Gardeners in northern regions typically remove suckers as soon as they appear even very early on.
No matter which method you choose, it’s wisest to remove suckers when they are very small. If you can pinch them off with your thumb and forefinger, and you won’t scar your plants.
If one does escape your notice and you need to cut it off, be sure that your pruner blade or sharp knife makes a clean cut.
Near the end of the growing season it’s a good idea to top off the plant. Prune off all the growing tips so the fruit remaining on your plant will ripen fruit before the first frost.
This works because cutting off the growing tips causes the plant to stop producing flower clusters and produce new fruit.
This directs all of its energy toward the remaining fruit. This causes faster fruit ripening.
Keep the Lower Parts of Your Plants Clean!
One very important aspect of pruning tomatoes to increase yield is to always keep the lower portions of the mature plant very thoroughly pruned.
Under no circumstances should your plant’s leaves ever be touching the ground. Keeping them off the soil will help keep them dry. This helps prevent disease.
Once a plant reaches a height of two or three feet, begun to produce blossoms and set fruit, cut off the foliage that is a foot or less from the ground.
This increases air circulation and helps prevent fungus spores from being splashed onto the lower leaves during rains.
This will help you avoid problems with tomato blight and a number of other common tomato diseases.