White Spots on Tomato Leaves| Top Causes & Remedies

White Spots on Tomato Leaves| Top Causes & Remedies

Joshua M. Riley October 2, 2023 5 min read

Have you noticed white spots on tomato leaves? If yes, your tomato plants are at significant risk of dying. Being a delicate plant, tomato leaves turning white may indicate some infections or external invasion. In this regard, you should first focus on unearthing the likely cause of white spots on tomato leaves and implement the ideal remedies afterward.

Usually, tomato leaves should naturally project a shiny green complexion. Depending on the exposure, tomato leaves may change color, which is not a healthy development. Developmental issues affect most plants that generate low production or die. Such problems include the white spot disease on tomatoes.

In this regard, it is essential to take the necessary measures promptly before the issue aggravates. The best thing is that you can remedy such an issue to restore the tomato plant’s production capacity. 

As a farmer, it is essential to understand the nature of the tomato plant and the threats surrounding its growth and production. Tomato plants are overly delicate and can be affected by various factors and exposures. Investing in ample information can assist in unearthing an organic solution for tomato leaf spots. You can also learn how to grow tomatoes indoors with lights here.

Causes of White Spots on Tomato Leaves

An individual can effectively answer the question of how to cure white spots on tomato leaves with adequate know-how of how the plant interacts with nature and other external factors. Several factors can cause white specks on tomato leaves and stems. Here are the leading causes: 

Extreme Exposure to Sun 

As much as sunlight facilitates photosynthesis, extreme exposure can harm tomato plants. White spots and holes on tomato leaves could result from excessive exposure of the tomato plant to sunlight. Scientific studies have identified sun rays as harmful to tender tomato leaves, especially to a high degree. 

In most cases, young plants are the most vulnerable to white spot disease tomatoes. The tender leaves are fragile, hence can only process moderate sunlight at a time. Transplanting young tomato plants directly to an open space with direct and extreme exposure to sunlight can lead to such defects. The primary concern is that the high fragility can lead to the death of tomato plants, especially at their tender age after transplant. 

When in the greenhouse, tomato plants are usually exposed to moderate sunlight throughout the early age before transplanting. That means radical environmental change, especially in extreme sunlight exposure, will lead to some growth defects. The sunburnt leaves begin by turning developing white spots and eventually shed when the condition persists. Shedding off leaves at an early age due to white spot disease on tomatoes leads to significant health issues, which limit the overall production. If some fruits have already formed, the tomato plant may develop blistery spots on the skin, which is equally detrimental to the plant. 

White Spots on Tomato Leaves- Fungus Infection 

One of the most dangerous causes of the destruction of tomato plants is fungal infections. In essence, fungal infection is the leading cause of white spots and holes in leaves. The fungal infection spreads at an alarming rate, causing extensive damage to the tomato plant, which may sometimes be irreversible. If you are wondering what white spots are on tomato plant leaves, then you should be quick to check if there is the formation of a fungal infection. 

Phytophthora Infestans spread fast on the stems and the leaves of tomato plants. It might take just a few days for the affected tomato plant to succumb to the infection, hence the need to implement timely remedies to avoid counting losses. It is also notable that infected plants can quickly spread fungi to others. Therefore, the need to act fast before extensive damage occurs. In some cases, fungi infection may eventually lead to stem rot, further damaging the tomato plant. The infected leaves shed with time to the extent that only stems are left. In other words, fungi infection is dangerous and can cause significant damage to your tomato farm. That’s why you need a DIY remedy for tomato leaf spots. 

Poor Interaction with Other Plants

Research has confirmed that what causes white spots on my tomato plant could be poor interaction with other plants. In this case, planting tomatoes and potatoes in the same place could lead to harmful interactions. What do white spots on tomato mean in this case? The two plants (tomato and potato) share common soil types and nutrients. When the two plants compete for common nutrients, the eventuality is that there could be white spots on tomato leaves. Notably, tomatoes are more fragile than potatoes. Therefore, it is easy for potato infections to affect tomato plants, leading to inhibited growth due to white spot formation on the leaves. 

It is also important to note that potatoes and tomatoes are susceptible to common diseases. That means that in the pursuit of competing for common nutrients, there is a high possibility that diseases could spread. Planted next to each other, potatoes and tomatoes easily infect each other. In this case, white spots on tomato leaves may emerge. 

White mold spots on tomato leaves -Powderly Mildew 

Powderly mildew is a common cause of white spot disease on tomatoes. Again, this is among the fungal formations that affect tomato leaves by turning them yellow or white, depending on the exposure. To unearth how to cure white spots on tomato leaves, you might consider fungal remedies to eliminate powdery mildew. 

Notably, powdery mildew strikes most when the temperatures are high. Growing tomatoes in hot and dry areas expose the plants to this risk. Powdery mildew forms grey dust on the surface of the leaves and gradually ‘eats’ in to develop white spots. In most cases, younger tomato plants are the most vulnerable to powdery mildew and fungus development on the leaves. Also, applying fertilizers can lead to powdery mildew, mainly when the environment presents the right combination. If not controlled, the powdery mildew can quickly spread to the leaves and the fruits. 

How to Prevent or Fix White Spots on Tomato Leaves- Top Remedies

The first and most crucial step in treating white spots on tomato leaves is identifying the cause. Once you know what causes white spots on my tomato plant leaves, the immediate action should be choosing the most effective approach towards achieving a lasting remedy. Your plants will thrive and yield the desired harvest with appropriate disease control. The good thing is that you can use home remedies for white spots on tomato leaves.

Treating white spots on tomato leaves may be a simple process depending on the magnitude of the case. In other instances, DIY remedies for tomato leaf spots may require some expert backup, especially when the issue is critical. Here are the most recommended approaches for preventing white spots on tomato leaves: 

Enhance Soil Quality 

Enhancing soil quality should be your priority if you want an organic solution for tomato leaf spots. Notably, nutrient deficiency is among the leading causes of white spots on tomato leaves. That means you can apply organic compost manure to enhance the soil quality, providing your tomatoes with a friendly growth environment. It is essential to ensure that the compost manure applied is healthy and does not negatively affect your tomato plants’ growth. 

Infections and diseases are usually prevalent where gardeners don’t practice crop rotation. For example, if the farm previously had potato plants, there is the likelihood that some contamination of the tomato plants may occur if the disease affected the previous crop. The idea is to consult an expert for soil quality evaluation to ensure there is no potential contamination and provide proper nutrients for the tomato plants. Evaluation and testing of the compost manure are equally essential to avoid instilling harm in your tomato plants. You could be wondering why white spots on tomato leaves are forming, resulting from compost manure contamination. 

Apply Fertilizer 

You could be wondering why my tomato leaves have white spots on them. One of the possible causes is that the soil needs more nutrients, hence the flawed growth process. A perfect alternative to compose manure is fertilizer. The good thing about fertilizers is that they are made procedurally and feature a well-articulated formula. That means you will have made a significant step toward effective tomato disease control upon selecting the right fertilizer. 

Getting an expert is a good idea to ensure you get the right organic solution for tomato leaf spots. In this case, the expert analyses the tomato plants and the soil composition. They advise on the fertilizer to apply from a professional perspective. Note that inappropriate application of fertilizers could further affect the tomato plant’s health. Therefore, an informed decision on the amount of fertilizer to apply is needed. Familiarize yourself with the different fertilizer options and settle for the best in controlling and preventing white spots on tomato leaves. 

DIY Remedy for Tomato Leaf Spots- Regulate Sunlight Exposure 

Among the core causes of white specks on tomato leaves and stems is excessive exposure to sunlight. In essence, sunlight is essential in facilitating photosynthesis. However, young tomato plants’ high degree of fragility does not allow excessive exposure to sunlight. Experts recommend a shady environment with moderate sunlight. Alternatively, consider growing your tomatoes in a greenhouse or tent. A greenhouse regulates the amount of sunlight reaching the plants. That way, treating white spots on tomato leaves becomes practical. 

Watering Tomato Plants 

When watering your tomatoes, you may notice a whitish matter. And this might have prompted you to wonder, what are white spots on tomato plant leaves? This condition can occur due to insufficient water supply for tomato plants. In essence, tomato plants are delicate and can only thrive in areas with a conducive and sufficient supply of water. The idea here is to ensure adequate irrigation for your tomato plants. However, water regulation is essential because excessive watering can compromise growth. Yellowing of tomato leaves can result from excessive watering. As much as water facilitates healthy growth, moderation is integral.

Apply Fungicide for Tomato Leaf Spots 

Notably, fungal infection is one of the most dangerous causes of white spots on tomato leaves. In this case, tomato plant care for leaf spots would be the most effective antifungal spraying. The good thing is that fungicides are abundant, so you can easily access some for your tomato plants. Treating white spots on tomatoes is possible when you eliminate the fungi. The idea here is to ensure the timely application of fungicides. That way, it can prevent white spots on tomato leaves from spreading further. Fungicides are considered a lasting remedy for treating white spots on tomato leaves. 

To ensure proper application, read through the professional manual provided with the fungicides. If the process turns tedious and frustrating, you can seek expert advice on applying a fungicide. Fungicide composition can be detrimental to tomato plants, especially when misapplied. 

Final Word

White mold spots on tomato leaves signify a possible defect in plant growth. To fix white spots on tomato leaves, identify the causative elements and choose the appropriate remedy. Remember, timely response is essential to ensure the problem doesn’t escalate, leading to the death of the tomato plant. 

FAQs 

Why are my tomato plants getting white spots on the leaves?

It’s easy to search for phrases like “why do my tomato leaves have white spots on them?” That’s because you don’t expect your tomatoes to have white spots. Generally, white spots on tomato leaves result from various factors, including excessive exposure to sunlight, lack of essential nutrients, overwatering, under-watering, and fungal attacks. If you notice white spots on tomato plant leaves, try the appropriate remedy discussed in this article to fix the white spots on tomato leaves. 

How do you fix white spots on tomato plants? 

Depending on the cause, you can treat white spots on tomato plants by applying fungicides, limiting sunlight exposure, moderating irrigation, and improving soil quality. The treatment you choose should depend on the cause of the problem. 

What is the best fungicide for tomato leaf spot? 

There are various types and brands of fungicides that you can use to control or treat white spots on tomato leaves. Most gardeners use home garden fungicides with chlorothalonil. Also, copper-containing fungicides can address the problem. Nevertheless, select fungicides with ample knowledge of how it works, the application intervals, and the procedure. 

Can I spray my tomato plants with soapy water or baking soda? 

Yes. You can use soapy water and baking soda on tomato plants. Veteran gardeners use baking soda, vegetable oil, mild soap, and water to create a solution for treating leaf spots in tomatoes. However, this solution requires regular reapplication to maintain efficiency. 

Which is the best fungicide for tomatoes? 

Any fungicide with chlorothalonil as the active ingredient is the best for tomatoes. That’s because you can apply this fungicide even a day before picking the ripe tomatoes. This chemical has low toxicity, and you can use it as soon as you subject your tomato plants to humidity or rain.