Tomatoes grown in pots require frequent watering because pots dry out quickly. Generally, you should water potted tomato plants daily at the soil level, ensuring the water drains through the pot's drainage holes. A mature tomato plant in a pot can use about a gallon of water daily, and in hot, dry conditions, watering twice a day may be necessary

. Key points for watering tomatoes in pots:

• Water daily to keep the soil consistently moist but not soggy.
• Check soil moisture regularly; if the top 2-3 inches of soil are dry, it's time to water.
• In very hot weather, water early morning and possibly again in the evening.
• Avoid overwatering, which can cause root problems and fruit issues like cracking.
• Use the finger test: if the soil feels dry a couple of inches down, water the plant

In summary, for tomatoes in pots, daily watering is typical, with increased frequency (up to twice daily) during hot, dry weather to maintain adequate moisture for healthy growth and fruit production.