Remember trying to dry trim some overgrown boxwoods last fall, made it look like a green snowstorm hit the patio. The vacuum was full of tiny leaves for a week. Switched to wet trimming after that, the clippings just stick together in a wet clump. So much easier to clean up.
Actually, wet trimming can spread disease between plants if you don't clean your tools (the water helps bacteria move around). I learned that the hard way after losing a few shrubs. Dry trimming is safer for the plants, even if it's a bigger mess for us. Maybe try a tarp underneath next time? You can just bundle the whole thing up.