Tomato Pruning Mistakes and How To Avoid Them.

This article would outline all the tomato pruning mistakes you must avoid so you are not left scratching your head wondering why the fruits are less than stellar.

To prune or not to prune…? This is somewhat a contentious issue among tomato growers with both sides advancing strong reasons for or against the practice. There is still a third group of growers who straddle both sides of the divide with the view that, like most things in life, the most satisfactory answers can be found in the middle and folks should stick to whatever works best for them.

But one thing that isn’t debatable is that ultimately, we all seek healthy plants and plenty of juicy tomatoes fruits at the end of the growing season.

Pruning tomatoes, like a host of tomato maintenance practices, is mostly about giving you the edge in terms of the bottom line of a better harvest.

Common Tomato Pruning Mistakes To Avoid

Before going into details of the various pitfalls to avoid while pruning your tomatoes, let’s look at the types of pruning for a better understanding of the issues at stake.

Types of pruning

Simple pruning – This is when the suckers, the shoots that grow between the stem and a leaf cluster, are removed completely from the growing plant.

This involves pinching each sucker at the base between the thumb and index finger. Then rocking it back and forth while pulling it gently until it snaps off the main stem. The resultant ‘wound’ left on the plant is small and should heal very quickly.

This is best recommended for suckers that are succulent and still very small.

Missouri pruning This form of pruning is recommended for larger suckers that have grown so fast you missed them when they were small.

Here, only the tip of the grown sicker is pinched off as opposed to removing it completely from the base. The remaining leaves can serve as shade to the plant and would help in producing energy for the plant.

Cutting just the tip in the Missouri method is necessary for a couple of reasons:

  • In the first place, if the matured sucker gets infected with a disease, just cutting the tip leaves the disease further away from the primary tomato stem
  • Removing the tip delivers less shock to the plant than cutting the sucker further down

While having more leaves means more cumulative energy for the plant, there is a downside to Missouri pruning. It is very common for new suckers to develop on the original one.

So you’d have to be vigilante to head them off before they become a problem. That means more maintenance chores for you.

Common Tomato Pruning Mistakes

Pruning determinate tomatoes

Pruning determinate tomatoes is easily one of the biggest tomato pruning errors. The intended benefits of pruning actually have the opposite effect on this variety of tomatoes.

Pruning won’t affect their size or the quality of harvest significantly. Apart from unnecessarily stressing the plant by cutting out suckers, the plant would not reach its full potential in terms of size, inevitably producing fewer tomato fruits.

If you have to prune determinate tomatoes (emphasis on ‘have to’) concentrate on removing only suckers below the primary flower cluster. You can also remove all leaves that look diseased as well as leaves that are touching the ground.

Finally, towards the end of the growing season, you can also prune late or new stems are known to weaken the older main stems. The later stage stems serve no useful function as they don’t live long enough to produce fruits

Pruning too many leaves: Aka Over Prunning! 

Pruning too many leaves from the tomato vine is an error that comes with serious consequences especially if you live in a hot area. You need to think in terms of how certain leaves act as shade to the fruits while preventing scalding from the summer sun.

Many tomato plants are known to fail when growers prune the vines severely. This wrong pruning practice exposes the plant’s interior to excessive sunlight leading to sunburn and ultimately death of the plant.

The best methodology is to prune about a third of the leaves on the plant leaving plenty to limit the effect of sunburn.

Pruning wet tomatoes

Pruning tomato plants when they are wet or when it’s raining is bad. The reason is simple.

Because wet tomatoes are prone to diseases, pruning while wet encourages the growth of various types of tomato microbes as well as spreading disease from infected plants to healthy ones via the splashing drops of water.

It’s best to wait until your plants are all dry.

Using wrong/unclean tools

You’d be surprised at the number of tomato growers that take this practice for granted. It is not uncommon for them to use any sharp, unsterilized object to cut larger suckers, diseased branches, or leaves.

First off, unclean tools can easily spread bacterial or fungal diseases to the plants. To prevent this, clean the pruning tool with a disinfecting wipe, hot soapy water, or diluted bleach. Do this after pruning each sucker, stem, or leave to avoid spreading disease.

Also, using tools that are not sharp would cause too much stress on the plant. The best tool for pruning suckers that are more than 2 inches long is the garden clippers, also known as pruners.

They are handheld tools that are easy to grasp and convenient for working in a tomato garden. Another reason to get a pruner is that the size perfectly matches tomato branches.

When going to get pruners, opt for the types commonly called bypass pruners. These are excellent for working in tight spaces and with live stems.

Wrong timing

When growing indeterminate tomatoes, it is wrong to wait for the plants to become established before you begin pruning stems that droop and touch the soil. Extension workers advise that the best time to begin pruning from the transplanting stage.

This is because stems and leaves that make contact with the soil are at risk of contracting soil-borne diseases. Even if the stems didn’t touch the ground, the fact they are close to the ground means mud can easily splash on them during rainfall or while watering the plant.

Another common timing error is the notion that you can prune at any time of the day. Like watering, the optimal pruning time is mornings or early evenings. Pruning in the middle of the day is stressful to plants like tomatoes.

Avoiding late-season pruning

Many tomato farmers don’t want to accept that the season is coming to an end and avoid effecting the necessary pruning to maximize output. This is wrong but understandable under the circumstances.

But avoiding this final pruning towards the end of the season could be the difference between hard, unripe fruits picked hurriedly before frost sets in and juicy ripe tomatoes fruits.

To get that last, all-important harvest for the Thanksgiving salad, prune the growing tip of the main stems a month before the first frost.

Removing the tips (also known as ‘topping’) helps to speed up the ripening of already existing fruits. Topping ensures that the plant stops flowering and instead focuses all resources and sugars produced to the remaining fruits to hasten the production of ripe fruits.

Important Pruning Tips

– For young indeterminate tomatoes, pruning should be done at least once a week in the first month because they grow very fast.

– Don’t cut suckers with a knife or razor. The stump left behind can become infected easily.

– If you decide to support the tomatoes with cages or trellises, install them before you start pruning.

– Trim the lower leaves while they are still young. Letting them grow first uses up plant resources needlessly. Besides, the wounds at this stage are smaller, heal faster, and are less prone to infection.

That’s all I’ve got to share on tomato pruning mistakes that should be avoided when pruning your tomato plant. Check the link below for other resources on tomatoes.

How to Grow Tomatoes on a Balcony

How to Tell Determinate From Indeterminate Tomatoes

Why Are My Tomato Leaves Curling?

When to Plant a Garden in Texas (Tomatoes, Vegetables.)