Tomato fruit
cracking is most likely to occur when the
movement of water and solutes into the tomato
fruit is rapid or protracted. Fruit are particularly
susceptible if physiological changes in
the tomato skin during ripening or under certain
soil moisture conditions reduce the strength
and the ability of the tomato skin to stretch. For
field-grown tomatoes, this most likely occurs
when low soil-moisture levels are suddenly
relieved by rain.