Seedlings started in the house
Seedlings started in the house for future outdoor planting. Some have leaves that curl under slightly. They are in a sunny window with extended lighting with grow lights.
Certified GKH Gardening Expert
Judging by the photo, the soil looks really moist. Is the soil damp to the touch? Perhaps you are over-watering them.
How close is your grow light to these plants? The heat from the grow light could also be the reason for the leaf curl.