DIY Remedies for Black Spots on Tomatoes: Healthy Harvests

DIY Remedies for Black Spots on Tomatoes

Although tomatoes are a popular crop in many gardens, they are unavoidably susceptible to a number of problems that may lower their quality and productivity.

Black stains that emerge on the fruits and leaves are a regular issue for tomato farmers.

These unattractive scars can be brought on by physiological conditions like blossom end rot as well as fungi diseases like early blight and septoria leaf spot.

This thorough tutorial will examine DIY treatments for tomato black spots so you can reclaim healthy harvests and take pleasure in your hard work.

Identifying the Causes

DIY Remedies for Black Spots on Tomatoes

It is important to comprehend the reasons of tomato black spots before looking at the cures.

Black lesions on leaves are frequently caused by fungi, such as early blight and septoria leaf spots, whereas dark spots on the bottom of the fruit are caused by blossom end rot.

You can correctly identify the issue affecting your tomato plants and take the necessary steps if you are aware with the signs and features of each issue.

Early Blight

Early blight, caused by the fungus Alternaria solani, manifests as dark, concentric rings on lower leaves, which gradually enlarge and turn black. Eventually, the disease may spread to the fruit, causing black spots to appear.

Septoria Leaf Spot

Septoria leaf spot, caused by the fungus Septoria lycopersici, results in numerous small, circular black spots on the leaves. As the infection progresses, the spots may merge, leading to yellowing and defoliation of the plant.

Blossom End Rot

Blossom end rot is a physiological disorder caused by calcium deficiency or irregular water uptake. It presents as dark, sunken spots on the bottom end of the fruit. These spots can enlarge, become leathery, and ruin the affected tomatoes.

Cultural Practices to Prevent Black Spots

DIY Remedies for Black Spots on Tomatoes
DIY Remedies for Black Spots on Tomatoes

Prevention is the key to maintaining healthy tomato plants and reducing the occurrence of black spots. Implementing good cultural practices can significantly contribute to disease prevention. Here are some essential practices to consider:

Proper Spacing and Airflow

Crowded tomato plants create an ideal environment for disease development. Ensure adequate spacing between plants to promote airflow and reduce humidity levels. Proper airflow helps dry out foliage quickly, making it less susceptible to fungal diseases.

Regular Pruning

DIY Remedies for Black Spots on Tomatoes

Regular pruning of tomato plants helps remove infected leaves and promote better air circulation. Focus on removing the lower leaves, as they are more prone to fungal infections due to their proximity to the soil.


Applying a layer of organic mulch, such as straw or wood chips, around the base of tomato plants can minimize soil splashing onto leaves and fruits. This reduces the chances of disease-causing pathogens splashing onto the plant.

Homemade Remedies

When it comes to tackling black spots on tomatoes, several DIY remedies can help combat fungal diseases and physiological disorders. Let’s explore some effective options:

Baking Soda Solution

Baking soda is a readily available household ingredient known for its antifungal properties. A simple baking soda solution can help control fungal diseases like early blight and septoria leaf spot. Here’s how you can prepare and apply it:

Step 1:

Mix 1 tablespoon of baking soda with 1 gallon of water in a spray bottle or garden sprayer.

Step 2:

Add a few drops of liquid soap to help the solution adhere to the plant leaves.

Step 3:

Thoroughly spray the solution onto the tomato plants, focusing on the leaves, stems, and fruits.

Step 4:

Repeat the application every 1-2 weeks, especially during humid conditions or after rainfall.

The alkaline properties of baking soda create an unfavorable environment for fungal growth, thus helping to control the spread of diseases.

Neem Oil Spray

Neem oil is a natural remedy that effectively controls fungal diseases and repels common tomato pests. It contains compounds that inhibit fungal growth and disrupt the feeding and reproduction of pests. Follow these steps to create a neem oil spray:

Step 1:

Mix 1-2 tablespoons of neem oil with 1 gallon of water in a spray bottle or garden sprayer.

Step 2:

Add a few drops of liquid soap to help emulsify the oil and improve its coverage.

Step 3:

Shake the mixture well to ensure the oil is properly mixed with water.

Step 4:

Spray the solution on the affected tomato plants, covering both sides of the leaves, stems, and fruits.

Step 5:

Apply the neem oil spray every 7-10 days, or as needed, to control fungal diseases and pests.

Neem oil is an excellent organic option that not only combats diseases but also acts as a repellent, reducing the chances of pest infestations.

Calcium Supplementation

Blossom end rot, a physiological disorder resulting from calcium deficiency or water imbalance, can lead to black spots on tomato fruits. Supplying adequate calcium can help prevent this issue. Here are two ways to provide calcium to your tomato plants:

Crushed Eggshells

Save and crush eggshells, then sprinkle the crushed shells around the base of the tomato plants. As the shells break down, they release calcium into the soil, making it available for the plants.

Calcium-Rich Fertilizers

Consider using calcium-rich fertilizers specifically designed for tomatoes or vegetables. Follow the instructions provided by the manufacturer to determine the appropriate application rates and frequency.

Calcium supplementation ensures that the developing fruits have sufficient calcium for healthy growth, minimizing the occurrence of blossom end rot.

Black Spots on Tomato Plants


Organic Disease Management

In addition to the DIY remedies mentioned above, adopting organic disease management practices can significantly reduce the chances of black spots on tomatoes. Here are some techniques to consider:

  1. Crop Rotation: Avoid planting tomatoes in the same location year after year, as this can lead to a buildup of disease-causing pathogens in the soil. Rotate your crops annually, preferably in a three-year cycle, to break disease cycles and maintain soil health.
  2. Companion Planting: Certain companion plants can repel pests or attract beneficial insects that prey on common tomato pests. For instance, planting marigolds or basil near your tomato plants can help deter pests and reduce the chances of disease spread.
  3.  Resistant Tomato Varieties: Selecting tomato varieties with natural resistance to fungal diseases can be an effective preventive measure. Look for varieties labeled as resistant to early blight or septoria leaf spot, and incorporate them into your garden.
  4. Removal of Infected Plant Material: Regularly monitor your tomato plants for any signs of disease. If you spot black spots or infected leaves, promptly remove and dispose of them away from your garden. This prevents the spread of diseases to healthy plants.

DIY Remedies for Black Spots on Tomatoes

Additional Tips and Precautions:

To ensure the overall health of your tomato plants and maximize your harvest, consider the following tips and precautions:

  • Proper Watering Practices: Maintain consistent soil moisture levels to prevent physiological disorders like blossom end rot. Water deeply and regularly, aiming for an inch of water per week. Avoid overwatering, as it can lead to root rot and promote fungal diseases.
  • Avoid Overhead Irrigation: Watering tomato plants from above can increase humidity and promote the spread of fungal diseases. Instead, opt for drip irrigation or watering at the base of the plants to keep the foliage dry.
  • Early Detection and Intervention: Regularly inspect your tomato plants for any signs of disease or distress. Catching the problems early allows for prompt intervention and a higher chance of successful treatment.
  • Safety Guidelines: When preparing and applying DIY remedies, always follow safety guidelines. Wear protective clothing, gloves, and goggles when handling and spraying solutions. Avoid contact with eyes and skin, and keep the remedies out of reach of children and pets.


Black spots on tomatoes can be a frustrating issue for gardeners, but with the right knowledge and remedies, you can regain control and enjoy healthy harvests. By implementing good cultural practices, such as proper spacing, regular pruning, and mulching, you can prevent the occurrence of black spots. DIY remedies like baking soda solutions, neem oil sprays, and calcium supplementation provide effective and organic options for combatting fungal diseases and physiological disorders. Also, organic disease management techniques, such as crop rotation, companion planting, and the use of resistant tomato varieties, contribute to long-term prevention. With these strategies and precautions in place, you can confidently tackle black spots on tomatoes and reclaim your garden’s productivity and beauty. Happy gardening!


  1. National Gardening Association:
  2. Gardening Know How: