Choose a location protected from high winds that receives filtered sunlight, such as on a porch. Place the plants in this location two weeks before you plan to move them outdoors permanently.
Leave the plants outdoors for two to three hours the first day. Bring them back indoors and place them back under the artificial lights for the amount of time they have become accustomed to.
Set the plants back in the protected spot each day over the course of the two weeks. Gradually increase the time they spend outdoors. Also increase the light exposure each day, until they spend they entire day outside in the sunlight. Decrease the amount spent under the grow lights as you increase the time spent in sunlight.
Decrease watering as you increase exposure. Don't allow the soil to dry out completely, but only water when the top 1 inch to 2 inches feels dry. Plants must tolerate both more sunlight and drier conditions in the garden bed.