Petunias generally require watering about once or twice a week, depending on weather conditions and whether they are grown in the ground or in containers. Here are the key details:

• In garden beds: Water deeply about once a week, soaking the soil to a depth of 6 to 8 inches. This encourages deep root growth and drought tolerance. Weekly watering is usually sufficient unless the weather is very hot and dry

• In pots or containers: Petunias need more frequent watering because containers dry out faster. Small pots may require watering every few days, and during hot spells, watering once or twice a day may be necessary

• Watering tips: Water when the top 1 to 2 inches of soil feel dry. Water deeply and slowly to saturate the root zone without drenching the foliage, which can cause disease. Morning watering is ideal to allow leaves to dry during the day

• During establishment: Newly planted petunias should be watered daily for the first 1-2 weeks to keep soil consistently moist, then reduce frequency as plants mature

• Adjust for climate: In dry or hot climates, increase watering frequency. In cooler or more humid areas, less frequent watering is needed

In summary, water petunias deeply once or twice a week in the garden, more often in containers, and always check soil moisture to avoid over- or under- watering.