blight remedies

Growing tomato plants in your garden provides juicy and plump fruit without having to make a trip to the market. blight and powdery mildew can attack the tomato plants, causing stunted growth, leaf discolouration, premature leaf dropping and discoloured spots on fruits.Water-stressed tomato plants are more susceptible than healthy, vigorous plants to diseases and pests. So if you have sandy soils or in a low rainfall area this disease could occur.

Having problems with tomato blight?

You don’t want to use harmful pesticides?

Types of Blight
Septoria leaf spot is caused by the fungus Septoria lycopersici, which attacks the lower leaves when the fruits have appeared. Leaves may wilt and die, leading to lower fruit yield, and fruits are more susceptible to sun scald. The Alternaria solani fungus causes early blight, which attacks the lower leaves with brown or black spots, eventually wilting and killing leaves. It can also attack and kill stems and occasionally infects fruits with sunken black spots that often cause the fruits to drop before they are ripe. Late blight is caused by the funguslike Phytophthora infestans. This organism attacks tomato plants during moist, cool weather and appears as dark green or nearly black spots on leaves. Late blight spreads quickly in wet conditions, and spots will soon appear on the fruit.
Fighting Blight
Blight spores can survive in the soil for three or four years. Only plant tomatoes in the same bed every three to four years, and remove and burn tomato refuse in the fall. Throw out and replace young transplants that appear to be in the early stages of fungal infection, and, if blight appears in young plants after transplanting, remove the infected leaves so that the spores do not make their way into the soil. When possible, water at the root, as moist leaves and stems are more vulnerable to fungal disease.
Recognise the Symptoms

Although it’s called late blight, this disease can strike at any time during the growing season, so inspect your tomato plants at least once a week for symptoms. Late blight initially shows up on the leaves as small green, water-soaked spots, but those spots quickly grow into purplish-brown, greasy-looking lesions. The undersides of affected leaves might develop rings of gray-white mold around the lesions. The entire leaf dies as the infection spreads rapidly to the stems and tomato fruit. Infected stems develop dark lesions, while affected tomatoes typically turn brown but tend to stay firm. Late blight symptoms can develop very quickly, turning entire tomato plants black and killing them within just a few days.

Respond Quickly
Fast action can slow and even stop late blight from spreading to the rest of your tomato plants. As soon as you spot late blight symptoms in your vegetable garden, immediately pull up the affected tomato plants; seal them tightly in plastic trash bags and place the sealed bags directly in a covered trashcan. Don’t compost any diseased plant tissue or you risk spreading the infection. It takes three to seven days for an infected plant to show symptoms, so inspect your remaining tomatoes every day for the next week to make sure they haven’t caught the blight infection.
Lower Humidity Levels

The late blight disease thrives in high humidity conditions. Watering the soil around the base of your plants with a soaker hose instead of using overhead watering methods helps reduce the air humidity level around your tomatoes. It also helps keep the foliage dry, which makes it harder for the blight pathogens to germinate and spread. Water early in the day to give the leaves a chance to thoroughly dry in the sunshine before darkness falls. Planting tomatoes in locations with well draining soil and ample air circulation can also reduce humidity levels around the plants while reducing foliage moisture.

1.Proper planting techniques can help prevent the development of tomato blight and stop the fungus from spreading to other tomato plants once it has started. Space tomatoes at least 3 feet apart to allow for good air circulation and quick drying time when leaves are wet.

2. Water the plants at ground level rather than from above, keeping the leaves dry. Splashing water moves the blight spores to other plants where they may become infected. Water plants in the early morning to allow the leaves time to dry before nightfall. Watering late in the day or in the evening keeps the leaves wet overnight and will promote blight growth.

3. Inspect the plants regularly for signs of blight. Early detection can help save plants and stop the blight spread. Early blight displays 1/2-inch-round brown spots on infected leaves; small 1/8-inch brown spots with gray centers and darker edges is evidence of septoria blight.4. Remove infected leaves as soon as they appear, cutting close to the stem with hand pruners. Discard damaged leaves to prevent the disease from spreading into the garden, and clean the pruners with a household disinfectant between cuts to stop the disease from spreading to other plants.

5. Collect and discard any diseased plant material from the surrounding ground. Splashing water may cause the spores to jump onto other plants and blight will overwinter in garden debris, quickly infecting new plants the following year. At the end of the growing season, remove and destroy all tomato debris to help prevent a recurrence of the blight. Remove and destroy any plants that show complete infestation.

6. Apply a fungicide. Once infected, the application of sulfur dust may help prevent the spread of blight to other leaves or plants. Regular fungicide application 2 to 4 weeks after transplanting the tomatoes into the garden will help prevent blight development. Apply the fungicide every 10 days throughout the growing season, ensuring complete plant coverage.


  • If growing tomatoes in pots, replace the soil each year to prevent blight development.
  • Refrain from planting tomatoes in the same spot each year; rotate their location to avoid any of the blight fungus that does overwinter in the planting area.
  • When planting tomatoes, add a layer of mulch to help prevent the amount of splashing that can occur when watering.


  • For personal protection, wear garden gloves when working with diseased or damaged plants.

Natural Remedies for Tomatoe Blight & Powdery Mildew
Baking-Soda Spray

Baking soda contains sodium bicarbonate, which has antifungal properties that can help naturally control early tomato blight, powdery mildew and anthracnose. Baking-soda spray consists of 1 tablespoon of baking soda mixed with 2 1/2 tablespoons of vegetable oil. Once you have thoroughly mixed the baking soda with the oil, add 1 gallon of water and 1/2 teaspoon of castile soap. For easier application, transfer the baking-soda mixture to a pump sprayer and thoroughly apply the spray to the tomato plants, ensuring the mixture covers both the upper and lower leaves as well as the soil. Multiple applications every 5 to 7 days may be needed in order to control the fungal disease. The baking-soda spray can be used as a preventive measure or to control the fungus at the first signs of infection.
Aspirin Fungal Spray

The aspirin used as an over-the-counter pain medicine helps to treat powdery mildew attacking your tomato plants. You must use uncoated aspirin tablets measuring 325 mg and dissolve two tablets in 500ml of water. A garden sprayer or squirt bottle works well to apply the aspirin spray to the tomato plants and allows you to thoroughly coat the entire plant, including the undersides of the leaves. If after a week powdery mildew symptoms persist, reapply the aspirin treatment to the tomatoes. According to the University of Florida, testing conducted by the University of Rhode Island concluded that tomato plants sprayed with the aspirin fungal spray yielded a higher crop than tomato plants treated with commercial fertilisers.
Tomato Virus Protective Spray

The tomato virus protective spray prevents several viruses from attacking tomato plants, including tomato leaf blight, tomato mosaic virus and spotted wilt virus. The recipe for this protective spray is 3.8L of water, 236.5ml of skim milk and 1/2 teaspoon of antitranspirant. Skim milk adds calcium, which is a common deficiency in tomato plants, and antitranspirant will protect the surface of the tomato plant from disease spores without interfering with the plant’s pores. When spraying the plant with the mixture, ensure you cover all areas of the tomato plant, including the undersides of the leaves.
Cultural Control

Providing proper cultural control will reduce blight and powdery mildew problems on your tomato plants. Crop rotation every year will help prevent pathogens living in the soil from infecting the tomato plants. Tomato plants need spacing of about 3 feet apart to allow for proper air circulation, which helps the foliage dry faster. Organic mulch added around the plants will protect roots while preventing fungal spores from splashing onto the plant. Forgo overhead irrigation and water at the base of the tomato plant. When blight or powdery mildew has infected leaves, immediately remove and destroy them to help prevent the disease from spreading.

Spray Plants with Copper

Spraying tomato plants with a copper-based fungicide often helps prevent late blight disease from occurring. Begin treatment when your local weather forecasts predict a prolonged stretch of wet weather. If possible, start spraying your plants about two weeks before late blight disease usually strikes your area. Repeat applications every seven to 10 days until the weather no longer promotes the disease or no more tomato plants have suffered with blight symptoms for at least a week. Following the instructions on the product’s label, use between 1/2 and 59ml of fluid copper product for each 3.7L of water. Spray your tomato plants thoroughly, including the tops and undersides of leaves. Reapply the fungicide if it rains within 12 hours of treatment.

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