An article of flashing for a deck includes a channel with a back leg, a first side leg, and a second side leg and further includes an attachment flange fixedly connected to the channel where the channel is adapted to receive decking. A deck flashing system includes a deck with a surface and at least one edge, decking forming the surface of the deck, and flashing extending along the at least one edge, the flashing having a channel adapted to receive the decking. A method of trimming a deck includes erecting deck framing, installing decking on the framing, and installing flashing on at least one edge or the entire perimeter of the deck.