Not ready to commit to ripping out your entire parking strip or building a big raised bed? You can take baby steps towards colonizing this valuable growing space by putting out a few inexpensive half-barrel planters to catch the sunlight for a small selection of veggies and flowers.
Here is an example from my neighborhood:
This garden is also on a fairly decent slope, so perhaps the ground had to be dug out a tiny bit so that they would be level. Other than that, it looks like they were pretty much just plunked down and planted.