Last year my brother built a raised bed in his yard and did very well with it. So it got me thinking, instead of using pots in the office, why not build a small, custom, raised bed that fits the windowsill? Something that would slide right into the space and use every bit of the growing area available. And since it would be fairly small, I could probably make it quite a bit deeper as well, perhaps a full foot or two.
OK all you engineering types, how would you build this structure? The element I feel I need to plan for most is drainage. It is an office space and I cannot afford to build a structure that will leak water, so I need to have some sort of drainpan built into the structure to catch excess water. Would you consider painting (part of/all) the sun-facing side black to warm the soil beyond the normal office temp of 74 degrees for plants that do better in warm weather?