The Q&A Archives: Tomato Blossom End Rot

Question: What can I do for blossom end rot on my tomatoes? They look very healthy, but they are getting a rot spot on the bottom. Not all are like this but quite a few.

Answer: Blossom end rot is basically caused by irregular watering and/or a calcium deficiency. It tends to occur when a long dry spell hits after a period when the plants have grown very fast or after a very wet rainy stretch. In other words, wide fluctuations in water availability can cause it. Try to ensure your plants receive a steady supply of moisture (if in doubt you can check the soil with your finger to see if it is moist or dry), mulch them well, and the problem should subside.

In addition, you might want to check your soil. Often, the best way to solve the deficiency problem is simply to keep the soil pH between about 6 and 6.8 as measured by a soil test. Soil test kits are commonly avalable at garden centers and through the County Extension. Your County Extension staff can help you with the test and interpreting the results and determining how to adjust the pH or add calcium if it is necessary. Your local County Extension can be reached at 863-0110.

The spot usually occurs when the tomatoes are about a third to half way ripe, so if you check them early you can remove the marred ones to preserve the plant's energy. Good luck with your tomatoes!

« Click to go to the homepage

» Ask a question of your own

Q&A Library Searching Tips

  • When singular and plural spellings differ, as in peony and peonies, try both.
  • Search terms are not case sensitive.

Today's site banner is by clintbrown and is called "Dicentra"