Potted herbs are more vulnerable than plants in the open ground and more dependent on your care. Pots can dry out quickly. During the hot weather check the soil every day. In autumn water only when soil is dry. Seedlings usually need daily watering. Herbs with large leaves,in active growth or in small pots also need frequent watering. Do not over water. Air is an important requirement for root hairs, and vital air pockets in the soil are eliminated by water logging, a perfect environment is created for root rot or fungus to thrive. Take care of your herbs and they will take care of you.