Mums generally need watering about once a week during the growing season if planted in the ground. However, potted mums require more frequent watering, typically every day to every other day, because they dry out faster. The soil should be watered deeply until moist, but the foliage should be kept dry to avoid fungal issues. It is best to water mums early in the morning and water when the top 2 inches of soil are dry to the touch. Overwatering and underwatering both cause yellowing leaves, so it's important to check the soil moisture carefully. Mulch on soil can reduce watering frequency by keeping the soil cool and moist.

Summary:

• Ground-planted mums: water about once a week deeply.
• Potted mums: water daily or every other day, check soil moisture often.
• Water early in the morning at soil level.
• Avoid wetting leaves to prevent disease.
• Adjust watering frequency based on temperature, soil type, and container size.