Tomatoes are a favorite in home gardens, loved for their rich flavor and rewarding yields. But when it comes to pruning, many gardeners either do too much or apply the wrong method altogether. While pruning can help manage growth and improve airflow, it’s not always necessary—and done incorrectly, it can actually reduce your harvest or make your plants more vulnerable to disease.
Here are five common mistakes gardeners make when pruning tomatoes, and what to do instead for a healthier, more productive garden.
1. Pruning Just Because It's “What You’re Supposed to Do”
A common belief among new gardeners is that every tomato plant must be pruned. In reality, not all tomatoes need pruning, and unnecessary cutting can do more harm than good.
Blind pruning can:
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Create open wounds, which invite bacteria and fungal infections
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Reduce the plant’s leaf surface area, limiting photosynthesis and fruit production
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Add stress, which slows down growth and flowering
What to do instead:
Only prune when there’s a clear reason—like improving airflow, preventing disease, or controlling size. If the plant is growing well and producing fruit, it may not need any trimming at all.
2. Pruning Determinate or Dwarf Tomato Plants
Determinate tomatoes grow to a set size and produce most of their fruit over a short period. Their side shoots—often referred to as “suckers”—are actually critical for fruiting.
Removing these branches leads to:
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Fewer fruiting stems, which directly reduces total yield
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Limited recovery, since these plants don’t keep growing indefinitely
What to do instead:
Avoid pruning major shoots or suckers on determinate and dwarf varieties. The only exception is removing lower leaves that touch the soil to reduce disease risk.
3. Skipping Tool Disinfection
One of the most overlooked mistakes in tomato care is failing to disinfect pruning tools between plants.
Dirty tools can:
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Transfer fungal, bacterial, or viral pathogens from one plant to another
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Cause disease outbreaks that could have been easily prevented
What to do instead:
Clean pruning tools with rubbing alcohol, disinfectant wipes, or hot water after each use—especially when moving between different plants. In humid conditions, this small step can save an entire crop.
4. Leaving Leaves Near the Soil
Lower leaves that touch or hover close to the soil are at high risk of catching soil-borne diseases like early blight or leaf spot.
This mistake can result in:
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Infections from water splashing contaminated soil onto the leaves
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Poor airflow, which creates a humid microclimate ideal for fungi
What to do instead:
Once the plant is 12 to 18 inches tall, prune off the bottom 6 to 8 inches of foliage. This creates a healthy buffer zone that keeps diseases at bay and promotes better air circulation.
5. Not Treating Pruning Cuts
Every cut made during pruning is a potential entry point for disease, especially during warm and humid weather.
Failing to treat these cuts may lead to:
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Fungal infections on newly exposed tissue
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Reduced plant vigor or even plant loss
What to do instead:
After pruning, apply a natural fungicide—like liquid copper—focusing on cut areas and the undersides of nearby leaves. Spray in the late afternoon or early evening to avoid sun damage and maximize effectiveness.
Final Thoughts
Tomato pruning isn’t about following rigid rules—it’s about understanding the plant’s growth habits, recognizing what it needs, and responding thoughtfully. Not every tomato plant needs to be pruned, and certainly not in the same way.
When in doubt, remember this: If there’s no clear reason to prune, don’t. And if you do, make sure each cut serves a specific purpose—whether it’s to improve airflow, support growth, or prevent disease. Prune smart, prune carefully, and your tomatoes will thank you with a bountiful, healthy harvest.
