A trellis system having a trellis structure that is installable to extend generally outwardly from a vertical supporting member. The trellis structure includes at least one internal mounting bracket by which the trellis structure is securable to the vertical supporting member. The internal mounting bracket has a unitary member having a flange portion and a web portion, the flange portion being securable to the vertical supportable member by fasteners and the web portion extending outwardly orthogonally from the flange portion and being couplable to one of the plurality of outwardly extending tube structures. A tube structure has a flange opening and a front opening sized to receive the web portion. The web portion passes through the front opening. The web portion has an alignment structure sized to be received within one of the outwardly extending tube structures in close fitting relation to an interior of the outwardly extending tube structure.