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How to Save an Overwatered or Underwatered Tomato Plant

Have you been caring for your growing tomato plants throughout summer, and now they seem a little wilted and drooping? There is nothing worse than seeing your garden suffering from too much or too little watering. Luckily, there is always something you can do to save your plants!

How do you save an overwatered or underwatered tomato plant?

  • An overwatered tomato plant shows signs of rotting and mold and, to save it, you will need to remove it from the ground and treat its roots before repotting it. 
  • If a tomato plant suffers from underwatering, it will show wilted, brown-spotted, and dry leaves, and it might need thorough rehydrating.

These tips are a starting point to get your plant back in its best shape in no time. However, there is a little more information that can help you treat your plant promptly. Learn to identify the symptoms of underwatering and overwatering, as well as how to handle an affected plant, below!

Symptoms of an Overwatered Tomato Plant

Learning how to water tomato plants correctly throughout each stage of their life might have been one of the toughest challenges you took up during your time as a gardener. 

However, many cultivators tend to overlook the impact that a mild frost or rainy weather can have on the wellbeing of the plants. Indeed, once you are comfortable with garden vegetable watering techniques, it is easy to forget to check whether the plant needs water or not. 

Overwatering is one of the most common mistakes and can quickly lead to the spoiling and early death of plants, both in containers and in the ground. Read on to learn what are the different symptoms that an overwatered plant will show.

Your plant is wilting and feels wet

Tomato plants will promptly respond if they are suffering from over or underwatering. The first critical telltale sign is in your plant’s look. 

Wilting plants are commonly associated with a lack of proper watering, but you can see a similar outcome in plants that are drowning. If you know what your plant looks like usually, you will be able to immediately notice that there is something wrong with the amount of water it is receiving. 

Touching the plant’s stems, leaves, and soil can confirm that the issue is overwatering. If they feel wet even during the day, this means that the plants have absorbed too much water that cannot be easily replaced or expelled through naturally-occurring transpiration.

Brown, drooping leaves

Brown and dropping leaves are tricky signals to interpret. If you have been caring for indoor plants, you might immediately recognize the sad look of your plant and associate it with a lack of water. 

However, before rushing to pour water near the plant’s roots, ensure that the soil is actually dry. In any other case, watering your plant might be counterproductive and even lead to an aggravation of the symptoms. 

Edema

Edema in plants is a condition derived from malabsorption of water and manifests itself through bumps, bubbles, and blisters on the leaves’ surface. 

External factors, such as improper watering and fertilization, can cause this condition to spread across your plant’s branches. While not life-threatening and easily curable, you will need to treat this disease promptly to restore the look and health of your plants. 

In this case, it is essential to understand that Edema derives from the fact that the plant is absorbing water faster then it can expel it. Increasing the amount of water fed to the plant can cause the leaves’ lesions to become worse over time.

Mold, mildew, and other fungal growth

While these symptoms are visible only after prolonged overwatering, they can be critical signs that your plant has not been able to process the amount of water received, and it is now drowning. 

The most common cause of spoiling is white mold, also called sclerotinia, that affects the stems and soil of the plant. Over 360 garden and crop plants are prone to this fungal disease, which gets the name of timber rot when noticeable on tomato plants. This dangerous condition can spread quickly across your crop, and it is usually due to your plant sitting in stagnating water for too long.

Rotten roots and foul odors

When your potted and in-ground plants sit in water for a long time, their roots will absorb an excessive amount of moisture that the plant cannot process. In turn, the water will stagnate in and around the roots, causing them to stop growing, weaken, and be more susceptible to pathogens. 

While diseases affecting the leaves and flowers of your plant might be more easily identifiable, rotten roots are more difficult to notice and treat promptly. some of the telltale signs of these conditions are:

  • Fleshy stems
  • White mold around the roots’ area
  • Rotten and foul odors coming from the plant
  • Leaves – both young and old – falling off the plant

Symptoms of an Underwatered Tomato Plant

Just as common as overwatering, failing to properly feed a tomato plant can cause it to die prematurely. Tomato plants naturally grow in climatic zones that present high temperatures, at least during the summer months. 

In such harsh conditions, it is easy to misjudge the amount of water they need, and the soil can end up drying off quickly. Rehydrating a wilting tomato plant is easy, but it is essential to identify the symptoms of such a condition to treat it promptly.

Slower growth

While you might not be monitoring the growth rate of your plants, you will be able to notice a more delayed development if the soil around them does not receive enough water. 

Tomato plants, just like the majority of trees, herbs, and fruit plants, absorb nutrients from the ground through the roots. Water, along with fertilizers, are the primary sources of minerals and essential compounds tomatoes need for healthy development. The roots of a tomato plant boast an average length of 20 cm (8 in), depending on the specific variety. 

After they have absorbed and processed the nutrients available in this area, tomato plants are not able to get any more nutrients. In turn, this lack of compounds can cause them to stop growing and developing.

Dry, discolored, and curling leaves 

The first signs of dehydration are visible in the leaves of your plant. The lack of water and nutrients can inhibit the photosynthesis process, preventing the plant from absorbing energy from the sun and producing vital energy. 

As a result, you will notice the leaves turning brown or yellowish, starting from the bottom of the plant and spreading upwards. Curling and dry leaves are also apparent symptoms that your plant is not getting enough water. 

Fail to flower

Another symptom associated with low levels of nutrients and minerals is the dropping of blooming flowers. In some instances, your tomato plant might fail to flower altogether. In turn, the lack of flowers can result in reduced productivity of the plant. 

If your plant is dropping early flowers or it is struggling to produce blossoms, you should expect a limited harvest. Even if treated promptly and correctly, this condition can cause you to see a late harvest towards the end of summer.

Dry Soil

Dry soil is one of the most common symptoms that your plant is lacking adequate watering, and it is also one of the most obvious ones. 

While the upper surface of the soil is usually not wholly moist, the potting mix should feel wet at touch at least two to five centimeters below the top. In container plants, you can see that the soil is now detached from the surface of the pot and seems to have shrunken.

How to Save an Overwatered Tomato Plant

Prevention and regular monitoring are the best ways to protect your tomato plant from the damage that overwatering can cause. 

However, you should water and fertilize it regularly but not excessively throughout your plants’ life. It is also essential to understand whether your plants are effectively in need of water. To do so, you should gain an understanding of the level of moisture of the soil. 

You can perform this task efficiently by sticking a finger in the ground. If it is still dry two to five centimeters below the surface, your tomato plant is ready for watering.

However, even the most expert gardeners can inadvertently misjudge the water requirements of a developing tomato. If your plant shows any of the symptoms of overwatering, there are some steps you can follow to save both your indoor and outdoor plants.

1. Eliminate stagnating water

Especially if you are attending an indoor potted plant, the first thing to do is remove the water that is sitting in the drip tray underneath the container. For outdoor plants, turn off any irrigation system you might have installed to water them automatically. 

2. Dig up your plant and remove it from the soil

If you notice signs of root rot, you will need to start treating your plant by removing it from the ground. This step might be more straightforward if you are dealing with indoor plants, as you can easily clean the roots from dirt and soil. Instead, regarding outdoor tomato plants, you will need to dig them out of the ground to analyze the damage.

3. Treat the roots

To treat the roots, start by removing residual soil and any additional dirt that is still attached to the hair and lateral branches. Proceed to cut off any spoiled or unhealthy root. While doing so, ensure to use clean and sanitized clippers or shears. 

This step is essential to avoid cross-contaminating the roots and potentially transmit other diseases to the plant. Moreover, you should opt for sharp cutting tools that won’t excessively damage the plant’s roots.

4. Let it dry

This step is strictly necessary only for outdoor plants but can be useful for your potted tomatoes as well. Exposing the plants’ roots to fresh air and sunlight can help them get rid of the excessive moisture they had absorbed. In the case of house plants, you could also opt to just transfer them into a new pot filled with drier soil.

5. Repot it or replant it

Leaving the roots out to dry for a while is also beneficial for the soil. Indeed, as the lower layers become uncovered, the moisture held underground evaporates quickly. 

Repot or replant your tomatoes into more suitable grounds and add mulch to regulate the level of moisture into the potting mix. If you are transplanting an indoor plant, pick a new potting mix that contains at least 1% of hydrogen peroxide. This substance can help regulate the aeration level of the soil and ultimately help with root oxygenation.

6. Resolving other issues associated with overwatering

Now that you know that your plant is safe, you might still need to deal with the side effects of overwatering such as Edema, bacteria, and mold. Here is what to do to limit the damage they can have on your plant.

  • Edema: Since Edema derives from malabsorption of water, helping the natural transpiration process can help. As the sun and heat cause the water in the leaves of your plant to evaporate, the plant absorbs fresh nutrients and moisture from the ground.

    To encourage this mechanism, expose your plant to a more intense source of natural light. Be mindful to do so gradually to avoid scalding the leaves. At the same time, ensure that the plant has availability of calcium and potassium, which can function as adequate protection against Edema.
  • Fungal diseases: Fungal diseases such as mold and timber rot can spread quickly across your crop. When you remove your plants from the potting soil to treat the roots, ensure that the fungus has not contaminated the soil. If you can notice moldy white spots, you should treat the area with fungicides and move your plant into healthier grounds.

How to Save an Underwatered Tomato Plant

Hydrating the tomato plant properly and regularly is vital to avoid underwatering it. However, if you forgot to nourish your tomatoes during the hottest summer months, there are quick solutions that can help you revitalize your plants in no time.

First off, you should avoid trying to compensate for the lack of moisture by pouring a large amount of water into the soil. Especially in container plants, the ground might be so dry to shrink away from the lateral surfaces of the pot. 

In this case, filling the gaps with water won’t rehydrate the plants and, instead, flow away from the container. Outdoors, the water will flow through the holes in the soil, away from the roots of the plant.

How to save an underwatered potted tomato plant

Rehydrating a tomato plant in a container is much more straightforward than treating an underwater one planted in your garden. Start by creating holes in the dry soil and breaking it apart. For this task, you could either use a fork or a small spade. In any case, you should be careful through this operation to not hurt the already-weakened roots.

Proceed to submerge the whole container in lukewarm water and wait until the soil is not producing air bubbles at the surface any longer. You can then drain the vase and prune away spoiled and unhealthy leaves and branches. 

Once that hardened soil can benefit from moisture, the plant should start to rehydrate and revitalize itself in a few hours slowly. To speed up the process, you could spray nebulized water on the leaves of your plant. 

This process’s length can vary depending on how damaged the plant was, and, in some cases, it might take up to thirty days to see a fully-healthy plant again. 

How to save an underwatered in-ground tomato plant

Saving an outdoor tomato planted in your garden might not be as easy. 

First, you should consider whether the plant is worth saving or if it suffered underwatering for too long. In case it is only showing the first signs of dehydration, proceed to provide shelter and shade from direct sunlight. 

Water the plants thoroughly and regularly to reinstate the essential nutrients the tomato plant needs. You could also opt to add moisture regulators such as plastic sheets and mulch. These agents will trap the moisture in, preventing evaporation. Even in this case, it is worth spraying the entire plant with water to moisten the dry leaves.

Final Thoughts

Learning how to water a tomato plant correctly is a hard task that can take you quite some time and a lot of practice. While tomatoes love fresh air, sunlight, and water in abundance, they are also delicate plants highly susceptible to external changes. 

Even though you might have learned that they need regular watering, you should always adapt the daily intake to the plant’s needs. Rain and humidity are alternative nutrient sources for a tomato plant and, by adding additional water to the soil after a rainfall, you could end up drowning it. 

Both underwatering and overwatering issues have secure solutions that can help you keep your plant alive without much effort. However, it is essential to recognize and treat the symptoms promptly.

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