Artificial lighting with full-spectrum CFLs and LEDs is for more energy-efficient than natural light for indoor plants.
Place artificial lights 6 inches over the plants. Either lower the containers as the plants grow, or raise the lights. That's why gardeners often have their lights on chains.
Some gardeners place aluminum foil or whiteboard on the surfaces around containers to reflect light. This lets you maximize the light by reflecting it back toward the seedlings.
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