To maintain your herbs, make sure to remove any seedlings that don’t seem to be thriving. This gives the thriving plants more room and access to nutrients because they don’t have to share them with other plants. Keep containers where they get at least 6 hours of sunlight but move them inside if there is a chance of frost. Don’t overwater them. Stick your finger about 1 to 2 inches into the soil. If it feels dry, it’s time to water your herbs. If you still feel some moisture, leave it be and check again later. Prune any wilting or broken leaves periodically so the healthier ones can thrive.