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Tomato Plants

Q.What Is Causing A Black Mold-like Substance In Tomatoes That Look Perfect On The Outside?

Zone Franklin TN | Anonymous added on July 11, 2021 | Answered

These are San Marzano tomatoes with plants that appear robust and many fruit. I have harvested only a few pounds, but have many green tomatoes. Two that I just cut open have a black mold-like substance on the seeds and flesh at the blossom end. What is causing this and can it be corrected?

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Certified GKH Gardening Expert
Answered on July 27, 2021

This sounds like Blossom End Rot! Ultimately, this is related to a calcium deficiency, but there are many reasons for this to happen. Here is an article that will help:


This article will help you to grow tomatoes to their potential:


This link will take you to a free ebook that you can download on the subject of tomatoes:


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