Answer: I've heard about commercial growers reducing water in late August to encourage fruit to ripen, but if you hold back on watering this early in the season, the fruits will not get the moisture they require to grow large. For largest fruits, thoroughly water each plant, making sure you apply enough to wet the entire root mass. One thorough soaking each week should provide enough moisture for a good harvest. If you have green tomatoes on your plants in late August and you want them to ripen before frost, you can stress your plants by withholding water. This will hurry the ripening process and may provide you with a few extra tomatoes before frost kills the plants.
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