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Tomato Blight - How to Prevent It, or Manage It

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One tomato plant killed-off by blight and one tomato plant behind it, doing quite well.

One tomato plant killed-off by blight and one tomato plant behind it, doing quite well.

This is the second time in my life where my tomato plants got blight and I am nearly heart-broken. Only one of my plants is dead, or nearly dead. The others survived and are doing very well but I am still upset seeing the life fading out of the one plant.

The first time it happened to my tomato plants was over fiver years ago. I did not know what it was, I did nothing about it and half-way through the summer all my tomato plants were practically dead. Now the situation is much different because I know what the discolouring of the leaves means. It's tomato blight, a fungal infection scientifically called Phytophthora infestans and it spreads by wind and water-splash.

This year it has been extremely humid, hot and windy. So, my main mistake was that I did not thin out the plants enough. I let them be quite bushy and that maintains humidity on the leaves. Together with the cold, windy nights, the humidity brought on the blight and at first, I did not catch on. I saw some leaves had spots on them and I thought that perhaps the sun was burning out the leaves but that doesn't usually happen. Tomatoes love the sun! I paid it no mind though and then, I saw the spots spread and increase in numbers on the one tomato plant and a few spots here and there on the other plants. At that point I knew it was blight and I reacted swiftly.

I moved the plant which looked the sickest by itself so its leaves do not touch the leaves of my other tomato plants and I started thinning-out the leaves and branches which looked infected. The best thing to do if blight appears on a leaf, is to go up the leaf towards the main stem, where You see there is no blight present and break it off. Usually three four inches away from the blight spots is good enough, to try to stop the spread throughout the whole plant.

I also began spraying the tomatoes. There are numerous options from your local gardening stores. I am not here to promote any particular company so I will leave names out. What I can say is that I make my own mix for preventing tomato blight and it works. I add one tea spoon (can add up to two depending on how bad the blight is) of baking soda, one teaspoon of dish-washing liquid and one tea spoon of olive oil to two liters of water (a regular big pop/soda bottle). I mix that, put it in a spray bottle and spray the leaves early in the morning. This has managed to save my other tomato plants from being covered in blight. Thank the Gods!!

So, perhaps people can learn from this. Do not give-up on your tomato plants even if they get blight. If You react quickly (unlike I did with the one plant), You can save your tomatoes! Remember, it's the humidity that creates the environment for tomato blight. Thus, thin out the plants and when watering try not to splash the leaves. Pour the water right by the stem, at the bottom and if You see white at first, then yellowish spots forming on the leaves start breaking-off sick branches and start spraying the tomato plants. That will stop the blight from spreading. I do wish this helps.

All the best to everyone!

This is what can be seen on leaves as blight starts attacking the plant.Cutting-off these leaves will help in stopping the spread.

This is what can be seen on leaves as blight starts attacking the plant.Cutting-off these leaves will help in stopping the spread.

A tomato plant which is doing quite well even though it also has blight but taking care of it has saved it.

A tomato plant which is doing quite well even though it also has blight but taking care of it has saved it.

How a healthy cherry tomato plant should look like.

How a healthy cherry tomato plant should look like.

Comments

Mr. Happy (author) from Toronto, Canada on August 03, 2021:

It's not that bad, Mr. Bill. I was actually just outside and collected a bowl full of cherry tomatoes. The really sick plant will be "put down" today. The rest of them I will take care of and they should be okay for another two months, until the summer sort of ends.

I am not giving up on tomatoes!! They're awesome. Thank You for the visit and comment.

Bill Holland from Olympia, WA on August 03, 2021:

I love growing tomatoes, but they are extremely hard to grow, at least for me. Thanks for the information, although I'm sorry you had to go through this in order to write this informational article. Sigh! Maybe I just won't grow them any longer. Why put myself through this frustration every year, you know?

Mr. Happy (author) from Toronto, Canada on August 02, 2021:

Yes, good advice Mr./Mrs. French, about disposing properly of the diseased leaves. I do know they can contaminate the ground if they are just left laying around. I burn them.

Thank You for the comment and good wishes. The weather has been tricky this year and that is affecting plants, for sure.

All the best!

Imogen French from Southwest England on August 02, 2021:

I've lost a few to blight myself over the years, it's horrible when it gets into the fruit. Make sure you burn or dispose of the diseased leaves and plants, so the spores don't go into the soil for next year. Good luck with your crop for this year.

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