Because blight can affect and spread to other tomatoes so quickly, learning how to identify, treat, and prevent it is critical for any tomato grower.
Tomato blight is caused by fungi that require moisture to grow. Once it starts, it can easily spread through wind, animals, and soil. To stop blight from affecting the rest of your garden, read on to learn how to identify, treat and prevent tomato blight.
Plant diseases are some of the most common garden problems, with blight being particularly frustrating due to how many types exist and how quickly they can spread.
Early blight symptoms will typically appear after the initial fruits begin to grow. The blight will start as small, brown lesions beneath the leaves and grow into target-like rings with dead tissue at the center. The tissue will yellow and die around the perimeter of the target lesion, leaving tomatoes vulnerable to sun scalding.
Late blight, unfortunately, can affect the plant during any time of the season and any stage of growth. You may notice white mildew growing along the darkening edges of the leaves, extending toward the stem. Unlike early blight, late blight can affect the fruit directly if left untreated.
Septoria is a very specific type of fungus that begins to show up when the initial fruits appear but will not affect the fruits directly. However, the leaves will be freckled with brown spots. As the spots grow, the leaves will die completely and fall off.
No matter what type of blight affects your tomatoes, the treatment is the same, and you need to act quickly to prevent further expansion. Spread natural mulch around the bottom of the plant to prevent any fungal spores from traveling to other plants as you remove all affected leaves. To ensure wind, water, or animals don’t spread the spores, burn the contaminated leaves.
If the blight has spread to more than just a few leaves, there is a natural way to treat your plants instead of using a fungicide. Two tablespoons of baking soda mixed with a few drops of dish soap diluted in a gallon of water can kill the blight. However, do not spray excessive amounts and do not spray it in direct sunlight, as it can become too strong and damage the plant.
To prevent blight from infecting your plants, you want to ensure as few spores as possible can reach the plant. Stake your plants so they grow up and away from the ground. Spread mulch around the plants so fungi cannot thrive in the soil. Additionally, use a hose instead of an overhead sprinkler to reduce the amount of stagnant water on the leaves and prevent spores from splashing around. If none of these treatments or prevention tips work, and blight keeps affecting your plants, consider growing a strain of tomatoes resistant to blight.
Now that you know how to identify, treat, and prevent blight, you can protect your tomatoes from unnecessary damage and even prevent blight from infecting other vegetables in your garden.