Flixy, patio gardening can be a tricky thing. If you want lush greenery and vibrant color in just one growing season, annuals are the best bet. If you have a naked wall, try putting up a lattice (can even prop it up if drilling violates your lease) and hang pots filled with trailing annuals. They will "cover" the lattice as they grow, and eventually make the wall a living canvas. Can hang some votive candles in the gaps, that looks really nice at night.

FYI, annuals in pots need water almost daily, and a fertilizer regime too, but the results can be fantastic. Happy planting!