If you were to use drift wood this would be awesome for a beach reception style thing. Very natural, but striking. Drill holes in wood, place tea lights. Beautiful outdoor table center piece for the picnic table---AROUND THE GARDEN POOL
If your deck or patio is partially covered, drape lengths of fabric or canvas between the joists to create shade. Space out the pieces of fabric for a more transparent look, and add lights to illuminate the space at night.