The AeroGarden should be placed in a bright, sunny spot. Make sure the light shines on the plants in direct sunlight. The best place for the AeroGarden is near a south-facing window. If you don't have a south-facing window, place it near any bright, sunny window.
Also, the lights inside the AeroGarden should be on for 16 hours per day. You can turn them off at night or let them run all night long.