How to Keep Your Tomato Plants Disease Free - Backyard Boss
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How to Keep Your Tomato Plants Disease Free

Tomato plants are a popular addition to most vegetable gardens. They’re easy to grow and store, the harvesting process is a breeze, and they require very general care to thrive. Unfortunately, like many outdoor plants, they can also be affected by a fair share of diseases.

However, there are several ways to combat and prevent these illnesses to make your harvest bountiful and delicious. Proper gardening techniques and plant care are the best way to help your plants thrive.

Below, you’ll discover the best tips for caring for and protecting your tomato plants, so they can remain disease-free throughout the season.

Tools You’ll Need

Tools for Tomato Plant Care
Image credits: Emmanuel Najera via Pexels

There are a few tools you’ll need to aid in the fight against tomato plant diseases. Check out the essentials, as well as a few optional items, below.

  • Baking soda (optional)
  • Companion plants (optional)
  • Pots with drainage (optional)
  • Watering can or hose
  • Mulch (optional)
  • Pruning shears
  • Bleach
  • Fertilizer

Methods For Keeping Your Tomato Plants Disease Free

Baking Soda

spade with pile of baking soda
Image credits: FotoHelin via Canva

Sprinkling baking soda around your tomato plants has many benefits, and one of them is preventing diseases. The baking soda creates an alkaline environment and increases the pH of the soil. This makes it difficult for fungus and diseases like powdery mildew and late blight to develop.

You can sprinkle baking soda around the plants or spritz a mixture of one teaspoon of baking soda and one quart of water onto the plants to prevent and treat fungal diseases.

Properly Water and Care For the Plants

Watering tomato plants
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Providing your tomato plants with the proper conditions is the best way to ensure they stay strong and healthy. Of course, this is beneficial for improving your harvest, but it will also mean they are less susceptible to disease.

Keep good circulation around the plants by opting for well-draining soil and placing the plants three to four feet apart. Also, water the plants in the morning and regularly enough to keep the soil moist while avoiding getting the leaves wet. Finally, plant in bright light with around six hours of sun each day.

Plant in Containers

young woman planting tomatoes plants to the paper pots. copy space
Image credits: Serhii Krot via Shutterstock

You can also plant tomatoes in containers to prevent disease. Keeping the plants separated will give you greater control over the soil’s moisture, plants’ location, and temperature conditions to help them thrive. Plus, you can easily handle diseased plants without worrying about their spread.

Provide Drainage

Growing tomato plants in straw mulch
Image credits: Spacemouse via Pixabay

Consider mulching to provide drainage that protects your plants from diseases. The mulch prevents soil from splashing onto the plant when watering, which limits the spread of disease and fungal spores. 

The mulch provides ample drainage to avoid overwatering, which can weaken and kill the plants. It also maintains moisture in the soil, limiting the need to water and even preventing weeds.

Lastly, mulching is a great way to keep your plants cool and protected for the heat.

Stay On Top of Pruning

Woman pruning tomato plant
Image credits: Anna Tarazevich via Pexels

Properly pruning your tomato plants improves air circulation, allows sunlight to reach the fruit, and prevents the spread of disease. Remove any diseased, dead, or yellowing leaves and foliage as soon as you spot them with a clean, sharp pair of pruning shears or scissors. 

Improperly pruning foliage can result in a weakened plant and wasted nutrients, so help the plant be as strong as possible by removing suckers, excess foliage, and any dying leaves you notice. These struggling pieces can take energy away from the overall plant.

Disinfect Tools

Cleaning garden tools
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No matter what you do to take care of your plants, improperly caring for your tools can result in the spread of disease. That’s why it’s crucial to disinfect your pruning tools, spades, tomato cages, and stakes with a solution of bleach and water.

The solution should be one part bleach and nine parts water. Wipe your tools clean between every cut when pruning and every use for other tools.


Fertilizing Tomatoes' plants
Image credits: encierro via Shutterstock

Along with the proper care conditions, fertilizer provides the plants with the nutrients they need to thrive. Your tomatoes will do well with regular fertilizing during the growing season, meaning they will become stronger to produce more fruit and fight against any diseases. You can DIY your own or purchase fertilizer at the store. Tomato plants are heavy feeders that enjoy plenty of nitrogen

Keep Your Tomatoes Happy and Healthy

These preventative measures are the best way to combat potential diseases, but you should always keep your eyes peeled for the eight signs your plants are sick. General care and maintenance is the best way to help your plants grow, but sprinkling baking soda around them is worth a shot as well.

Will you use any of these methods to ensure your tomato plants remain disease free? Share in the comments below!