How To Prevent and Treat Early Blight on Tomatoes - Backyard Boss
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How To Prevent and Treat Early Blight on Tomatoes

Early blight is a very common killer of tomato plants every year, but there are ways to prevent it and treat it if you do catch it in time. If you grow tomatoes in your garden each year, knowing the signs of early blight are important. Here are a few tips for preventing this disease and how to treat it if your tomatoes are infected.

Early blight
Image credits: travenian via Canva

About Early Blight on Tomatoes

Early blight is one of the most common tomato and potato diseases. It can affect the tomato plants’ leaves, fruits, and stems and can seriously affect the growth of the fruit. Early blight will cause the leaves to completely fall off and the sun will start to burn the tomatoes. Early Blight is caused by fungus and bacterial infections. Fungal and bacterial blights tend to happen under cool damp conditions.

Recognizing The Signs of Early Blight

Symptoms of early blight first appear at the base of the tomato plants. They will look like circular brown spots on both the leaves and stems. The spots will start to get larger as the infection worsens and the spot develops concentric rings, giving the appearance of a target with a yellow halo. Another sign that the infection is worsening is multiple spots on a single leaf, then killing the leaf off completely. Early blight can lead to the death of your tomato plants.

If you have had to remove your plants due to early blight make sure to rotate because early blight does infect soil and your new plants can become infected if they touch contaminated soil.

early blight developing on plant leaf
Image credits: travenian via Canva

How to Prevent Early Blight On Tomatoes

Since early blight is so common on tomato plants and how quickly it can destroy your plants, it is good to know how to prevent it. There are a few things you can do in your garden and an easy thing to start off with is covering the soil under your tomato plants with mulch, and there are many different varieties to choose from (organic, inorganic).

Another way to prevent early blight is to make you are always water at the base of each plant, being careful not to overwater or let water collect on the leaves. Letting water pool around the bottom of the plant and on the leaves can cause a number of different problems for your plant so it’s best to avoid it altogether.

Pruning the bottom leaves of your plant can also prevent early blight and its spores from splashing up from the soil onto leaves when you water your plant.

Another thing you can do to help prevent early blight is to increase the airflow by trellising your plant, removing weeds and dead leaves, and spacing plants apart giving them plenty of room to grow. This will keep your soil healthy and in turn keep your plant healthy.

And each season when you’re about to plant your garden again make sure that it has been at least two years before you plant tomatoes in the same spot.

Watering seedling tomato plant in greenhouse garden with red watering can.
Image credit: Fotokostic via shutterstock

How To Get Rid of Early Blight

Managing or getting rid of early blight can be difficult but there are some things that can be done. The first thing you should do when managing early blight is cut leaves with leaf spots and get rid of them. Do not leave them in the soil or near the plant. If you touch the infected leaves, make sure to wash your hands well before working in healthy tomato plants. If you use tools, you will need to wash and sanitize them as well when you are done so they do not infect any other plants. Note, many other plants can be infected with early blight, not just your tomatoes.

When trimming your plant to remove all infecting or dying leaves, stems, and fruit, it is okay to remove up to one-third of the plant’s leaves. Removing more than one-third of the plant’s leaf will risk killing it. After removing all the dead and infected leaves make sure to keep leaves dry to reduce the spreading of the disease. You will also want to keep fertilizing your plant.

Another way to fight early blight is to thoroughly spray your plant with a fungicide like Bonide Liquid Copper Fungicide concentrate or Bonide Tomato & Vegetable. Both of these treatments are organic and will not harm your plants. Wait 24 hours after spraying your plants and remove the lower branches and leaves. Repeat this treatment after 7-14 days, or as the label directs you to.

Pro tip: Make sure not to use fungicides in weather warmer than 80 degrees.

Treat Your Plants

Well there you have it, what to look out for with early blight, and how to prevent, manage, and fight it if your tomato plants were to get infected. ¬†Early blight might be a common killer of tomato plants but it does not need to kill your plants. Just look for the early signs and you’ll have a better chance of saving your plants.