Our tomatoes are late by a month because the warm weather came late. In the last few weeks, I notice that my green tomatoes are getting brown patches (see picture) and would rot before ripen. Some of the green tomatoes I picked earlier to be ripen indoor looked fine and a few days later, some will get brown patches as well.

This seems to be happening to tomato plants that get a daily 10 minutes watering from my sprinkler system. I have 2 plants that do not get watered automatically are doing the best of all....no brown patches. Am I over watering them??

what should I do different next year??

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