After a few weeks I realized the natural light wasn't cutting it. I made these simple shelves out of half inch maple (the same stuff the planter boxes are made out of). I mounted a 2 bulb (T8) fluorescent fixture under each and did my best to hide the cords. Hopefully this will be enough light for them.
Ushio BC2771 USHIO G10T8 9.5W Germicidal Low Pressure Mercury-Arc Lamp. Hid bulbs produce high output for their size making them a compact powerful & efficient light source. Hid bulbs are used for general Lighting, professional Lighting Fixtures, growing applications. Hid bulbs put out around 3-5 times greater output (lumens per watt) than traditional halogen bulbs. Ushio bulb, 9.5W. Base: G13 2-pin, rated life (hours): 8000, color Temp:, luminous flux (lm).