Help - my tomatoes are turning brown on the bottom. This one plant out of 15. It's not every tomato on this plant. Maybe 1/3 have this problem. t's an heirloom, brandywine. I am in zone 9b. This just happened in the last couple of days. I have a drip system and all my other tomatoes are doing well. But we have had a sudden heat wave of 100 plus days for the last 3 days. Is it disease or a heat/water issue? Should I quarantine? It is in a fabric pot so I can move it.

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  • Usual cause of blossom end rot is insufficient water, which disables calcium uptake, so yea, the heatwave meant this one needed more water
    – Bamboo
    Jun 20, 2017 at 9:41

2 Answers 2


Blossom end rot. It's caused by a calcium imbalance. It can be because of calcium deficiency, but also other reasons such as soil PH and watering. In your case it is likely to be due to the heat wave.


I thought I'd send a recipe for management. Be nice to see your entire plant, to know whether it is in sterile potting soil if it is in a pot, if not what type of soil you do have, raised beds? Watering practices and most certainly what you are using for fertilizer. This link should help or even engender more questions.tomato end rot Just adding calcium might not help at all. You need to test your soil's pH and give us the formulation of your fertilizer. Any additions such as manure?

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