The answer to this question is dependent on a variety of factors, including the size of your tomato plants and the weather in your area. If you live in an area with hot summers, frosty winters, and little rain, you should water your tomato plants every day.
If you live in an area with mild winters, and a year-round rainy season, you should water your tomato plants once every two to four days. If the weather is very dry and sunny, you can water your tomato plants as often as once a week.
You should also pay attention to the soil conditions when watering your tomato plants. Tomato plants that are planted in sandy soils tend to need more frequent watering than those planted in heavy clay soil or loamy soils.
And You have also checked the moisture levels in your tomato soil regularly, as well as the amount of sunlight reaching through the soil to see if it needs more water.