Answer: Some tomato varieties naturally develop splits at the stem end, which does make the fruit look rather rugged, but they still taste good. Other times the cracking or splitting is caused by hot weather and moist soil. The plants take up more moisture than the fruits have room to store, and the skins split because of the uptake of moisture. There's not much you can do about this other than to grow varieties that are bred not to split. Hope this answers your question.
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