Circular or radial cracks mar the stem end (top) of ripening fruit. Cracks may extend deep into the fruit, causing it to rot.
Tomatoes crack when certain environmental conditions encourage rapid growth during ripening. The rapid growth is frequently promoted by a drought followed by heavy rain or watering. Tomatoes are most susceptible to cracking after they have reached full size and begin to change color. Some varieties crack more easily than others. Cracking is more severe in hot weather. Some cracks may be deep, allowing decay organisms to enter the fruit and rot it. Shallow cracks frequently heal over, but may rupture if the fruit is roughly handled when picked. Cracked tomatoes are still edible.
Maintain even soil moisture with regular watering, according to the instructions in Tomatoes. Grow crack-tolerant varieties.
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